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Capturing Solar Power With Antennae

necro81 writes "Researchers at the University of Missouri and the Idaho National Laboratory have demonstrated a new method of capturing solar power. Rather than using semiconductors to capture photons of sunlight, they fabricated small coiled antennae (several um square) that resonate with the wave nature of light. The antennae are tuned towards midrange infrared light (5-10 um), which is abundant on our cozy-warm Earth — even at night. They also demonstrated a way to imprint these coils on a substrate, like how CDs or vinyl records are produced, but could be scaled to roll-to-roll mass production. The usual caveat applies: it may be 5-10 years until this could hit the market."

190 comments

  1. As long as its not 7 years away... by RandomChars · · Score: 0
    1. Re:As long as its not 7 years away... by uhoreg · · Score: 1

      I think this is a more relevant comic: http://xkcd.com/678/

      --

      To get something done, a committee should consist of no more than three persons, two of them absent.

    2. Re:As long as its not 7 years away... by jemtallon · · Score: 1

      I concur. Original post is dated 2008... so their prediction is now 7 years away, making it made up

    3. Re:As long as its not 7 years away... by Anonymous Coward · · Score: 0

      Ah, but don't forget the researcher translation

    4. Re:As long as its not 7 years away... by TheTurtlesMoves · · Score: 1
      --
      The Grey Goo disaster happened 3 billion years ago. This rock is covered in self replicating machines!
  2. And 5-10 years from now... by elrous0 · · Score: 3, Interesting

    It will still be 5-10 years away.

    --
    SJW: Someone who has run out of real oppression, and has to fake it.
  3. Antennas by LearnToSpell · · Score: 5, Informative

    Antennae are for bugs.

    1. Re:Antennas by Anonymous Coward · · Score: 0

      Thank you, you saved me the trouble.

    2. Re:Antennas by icebraining · · Score: 1

      Thank you. They even use Antennas in TFA, so why did the submitter screw up? I know, I must be new here.

      Appropriate username, btw.

    3. Re:Antennas by mattack2 · · Score: 1

      Says who?

      http://www.merriam-webster.com/dictionary/antenna
      shows antennae as the first plural listed (which usually means it's the preferred one). Strangely, the two other definitions have antennae *repeated* as the plural in the definition.

    4. Re:Antennas by IceFoot · · Score: 1

      ``Yeah, we don't use "antennae" 'round here.

      What is with people who insist on the -ae?

      IT'S ANTENNAS, FOLKS!!!

    5. Re:Antennas by guruevi · · Score: 1

      And David Bowie's nipples.

      --
      Custom electronics and digital signage for your business: www.evcircuits.com
    6. Re:Antennas by Anonymous Coward · · Score: 0

      The word "antenna" is used for both "antenna" and "aerial" in America. In the Queens English, however, there is a distinction.

    7. Re:Antennas by georgesdev · · Score: 1

      check http://en.wikipedia.org/wiki/Antenna
      antennae is a biology term. learntospell = 10 points ;)

    8. Re:Antennas by Anonymous Coward · · Score: 0

      It's virii all over again, you douchebags keep claiming it is right, even though you know it's wrong.

    9. Re:Antennas by bjohnso5 · · Score: 1

      This. Flight of the Conchords reference for the win.

  4. Most important point not in summary by GameboyRMH · · Score: 3, Insightful

    The summary fails to mention the most important advancement here: 90%+ efficiency. That's a game-changer for solar power.

    --
    "When information is power, privacy is freedom" - Jah-Wren Ryel
    1. Re:Most important point not in summary by joe_frisch · · Score: 5, Insightful

      What are they using to rectify the signal to convert to DC? The antenna is neat - but not at all surprising, its size should just scale with wavelength. You could make a 125nm long antenna that would resonate with visible light (well withing the resolution of existing lithography). The problem is how to convert the 100THz signal you get to a DC signal. You need a fantastically fast diode.

      If they have managed this, that would be an impressive achievement. The fastest diodes I am aware of are around 1THz, but its well outside my field and there might be something faster out there

      BTW: the efficiency isn't all the impressive. For single frequency light, conventional solar cells can be quite efficient (~80%???), but they don't do will with broad thermal light (like sunlight). The photons that are less than a band-gap don't do anything, and the ones above a bandgap waste any excess energy.

    2. Re:Most important point not in summary by drerwk · · Score: 1
      The P fails to notice that they are not yet able to rectify the current, and hence can not yet get power out, and so the 90% number is only for antenna coupling, not conversion to DC current.

      More extensive research needs to be performed on energy conversion methods to derive overall system electricity generation efficiency.

      It is like saying current solar cells are 90% efficient because 90% of photons are absorbed; it says nothing about the quantum efficiency of conversion. I am willing to bet that the QM Efficiency of the necessary rectifier will be the big loss; though it may only be 50%.

    3. Re:Most important point not in summary by Anonymous Coward · · Score: 0

      Unfortunately that's not across the solar spectrum but in a small band in mid-IR that is very low in actual power from the sun. I saw the 90% quoted on another site erroneously.

    4. Re:Most important point not in summary by Anonymous Coward · · Score: 0

      90% for that range of frequency which i bet is quite small in comparison to regular solar power. This definitely sounds like a good possibility but the total energy they can get is from a smaller pool though this may not matter due to higher efficiency but most importantly, cheapness.

    5. Re:Most important point not in summary by Brett+Buck · · Score: 4, Informative

      I think you see the problem - I *am* in a related field and I certainly don't know of any practical or efficient way to rectify it. I can think of absurdly inefficient ways, but we already have a bunch of those.

    6. Re:Most important point not in summary by lupine · · Score: 3, Insightful

      From TFA:
      The individual nantennas can absorb close to 90 percent of the available in-band energy.

      So the total system efficiency depends on how wide that band is in relation to total solar energy available and whether nantennas can be stacked and designed to capture energy over a range of bands.

    7. Re:Most important point not in summary by dbc · · Score: 1

      Yes, antennas tend to be very narrow band. Rectification is the key here... I remember hearing about somebody using nano-antennas to capture solar energy in the early 80's... back then, though, they figured they were 5-10 years away from having something ready for the market.

    8. Re:Most important point not in summary by blair1q · · Score: 2

      Solar efficiency is measured as usable power output vs. total incident power across the full incident spectrum.

      This thing's efficiency is measured as usable power output vs. power across the very small bandwidth it detects. Which is to say, its solar efficiency is probably in the micro-percents.

    9. Re:Most important point not in summary by chemicaldave · · Score: 1
      Alas, the authors mention this indirectly. Emphasis mine:

      More extensive research needs to be performed on energy conversion methods to derive overall system electricity generation efficiency. ... This research is at an intermediate stage and may take years to bring to fruition and into the market. The advances made by our research team have shown that some of the early barriers of this alternative PV concept have been crossed and this concept has the potential to be a disruptive and enabling technology.

      At least they made actual progress in this paper with real models. That's more than can be said for the hundreds of theoretical models.

    10. Re:Most important point not in summary by Anonymous Coward · · Score: 1

      How about.. have two slightly different antenna sizes on the substrate. Mix the super high frequency stuff together to get a beat frequency you can rectify with cheap and cheerful silicon diodes.

      Probably a million reasons why it won't work, but I may as well throw it out there...

      ( If it does trigger the solar revolution and somebody gets very rich, don't forget to send some my way ;-) )

    11. Re:Most important point not in summary by CCarrot · · Score: 1

      90% for that range of frequency which i bet is quite small in comparison to regular solar power. This definitely sounds like a good possibility but the total energy they can get is from a smaller pool though this may not matter due to higher efficiency but most importantly, cheapness.

      Actually, it sounds like by varying the size and materials of the antennas on a panel, they can capture a much broader spectrum of light than 'conventional' panels, including extending into the infrared.
      https://inlportal.inl.gov/portal/server.pt?open=514&objID=1269&mode=2&featurestory=DA_101047

      There are definite and novel uses for this, if they could figure out how to actually rectify the electricity generated. Industry, for example, spends big dollars trying to shed waste heat from piping and equipment...how about wrapping it in one of these and let the generated electricity run your cooling system for you? Talk about direct waste heat recovery systems...I picture a solar farm with their 'panels' gently flapping in the breeze, not caring about incident light direction, so long as they're in the sunlight...and still keeping the lights on for some time after the sun goes down...

      good times.

      --
      "I love animals! Some are cute, others are tasty, what's not to like?" - Betsy Schroeder, Jeopardy contestant
    12. Re:Most important point not in summary by nanohurtzGT · · Score: 1

      Nothing new, this was developed years ago, and took the approach of microvibrators. If only this were a resource based economy. This would hit the market tomorrow... * tosses the idea with the rest of the pile including the flying car, and the transatlantic super train *

    13. Re:Most important point not in summary by mldi · · Score: 1

      I would imagine this is why we aren't powering space stations on the dark side of earth with giant laser beams? Because that idea tickles me.

      --
      If you aren't suspicious of your government's actions, you aren't doing your job as a responsible citizen.
    14. Re:Most important point not in summary by skids · · Score: 3, Interesting

      Such a system would be yet another layer in the panel to deal with a specific frequency range. Perhaps several layers with different wavelengths in each. It's journalists that make the mistake of promoting this as a whole solar panel.

      That said, the rectification issue is a deal killer. Not only are we talking THz, but IIRC from the last media go-round with this technology, voltages way below practical diode thresholds.

    15. Re:Most important point not in summary by pz · · Score: 2

      Might there be an efficient way to frequency scale the signal and bring it down to usable levels? Or does the fact that we're talking about light-scale dimensions mean most of what we think about in terms of EE is not applicable?

      --

      Put my fist through my alarm clock with its ding-dong death inside my ear. - The Blackjacks.
    16. Re:Most important point not in summary by Em+Adespoton · · Score: 1

      Seems to me that once they get a decent diode, these could be used as air cooling systems, with generated power as a positive side effect.

    17. Re:Most important point not in summary by Anonymous Coward · · Score: 0

      But that's not overall efficiency, mind you. 90% of the energy in the band that resonates with the antenna is collected. Then electrons still have to go through a rectifier. All in all, efficiency should be better than actual photo-voltaic cells, but not that much better.

    18. Re:Most important point not in summary by jcr · · Score: 1

      Isn't that only for the particular band it's tuned to absorb?

      -jcr

      --
      The only title of honor that a tyrant can grant is "Enemy of the State."
    19. Re:Most important point not in summary by LWATCDR · · Score: 1

      What about doing the reverse? Use this to produce light? Maybe for a monitor or screen. Yes no the problem is to make a lot of really cheap transmitters. Maybe really tiny magnetrons?

      --
      See my blog http://ilovecookes.blogspot.com/ for light hearted technical information.
    20. Re:Most important point not in summary by whiteboy86 · · Score: 1

      Not 90% efficiency over whole light energy spectrum, but in a certain frequency band the antenna is tunned to, that means 90% efficiency in a narrow band of light energy.

    21. Re:Most important point not in summary by Anonymous Coward · · Score: 1

      But then you'd need a super-high-frequency mixer...

    22. Re:Most important point not in summary by i_b_don · · Score: 2

      What? Best in class photovoltaic solar cells, in university settings under optimal conditions are around 43%-44%. That's the top efficiency of some very complex structures that are not mass producible using a light source that's 80x normal. 80% is unheard of. In fact, as I was thought in school 15 years ago, the theoretical maximum efficiency of the transistor solar cell method is 50%, thus the reason that 43% is considered really damn good. 80% is god-like.

      d

      --
      all language nazi's will burne in heil!
    23. Re:Most important point not in summary by wagnerrp · · Score: 1

      This is nothing more than a rectenna, scaled down to operate at optical wavelengths. Rectenna in the microwave band already operate with 85-90% usable generated electricity. The problem is that while we have electronics fast enough to rectify a microwave signal in the tens of GHz, we have nothing that even comes close to rectifying an optical signal in the hundreds of THz.

    24. Re:Most important point not in summary by Nethemas+the+Great · · Score: 1

      I'm totally out of my depth on this (so please forgive my ignorance...) but perhaps if I'm understanding properly we've already got a start on rectifying THz radiation.

      --
      Two of my imaginary friends reproduced once ... with negative results.
    25. Re:Most important point not in summary by Rei · · Score: 1

      I can't help but wonder about the entropy aspect. I mean, you're taking away blackbody radiation and turning it into power at extreme efficiency so that you can get work done all over again. Doesn't that strike anyone else as odd? I mean, let's say that you've got an engine near the Carnot limit and you wrapped it in these IR solar cells, which take 90% of the radiated waste heat and turn it into electricity, when you then use to power an electric motor to boost your engine's output. Would you not have just surpassed the Carnot limit?

      --
      Could chocolate let me finish?
    26. Re:Most important point not in summary by Plammox · · Score: 2

      If the two different frequencies you pick up are not in phase and coherent (sunlight isn't, to my knowledge), then you won't get a beat frequency.....sadly. Nice try.

    27. Re:Most important point not in summary by Anonymous Coward · · Score: 0

      I'm probably missing something, but why not a traditional AC transformer and transform it to 230V AC or whatever?

    28. Re:Most important point not in summary by Obfuscant · · Score: 2

      If the two different frequencies you pick up are not in phase and coherent (sunlight isn't, to my knowledge), then you won't get a beat frequency.....sadly. Nice try.

      If there are two different frequencies, they can't be in phase and coherent. Even a harmonic will be 180 degrees out of phase some of the time.

    29. Re:Most important point not in summary by avandesande · · Score: 1

      It's pretty easy to convert visible light into infrared- ie black paint. I doubt it would be hard to find a material to do it in a narrow range....

      --
      love is just extroverted narcissism
    30. Re:Most important point not in summary by joe_frisch · · Score: 1

      AC transformers don't change the frequency. You would end up with few x 100THz power - eg. light. Basically the same as using a fiber to move the sunlight somewhere else - you still need to convert to DC for most applications.

    31. Re:Most important point not in summary by Anonymous Coward · · Score: 0

      problem is that you don't want the signal but the power. Mixing this towards lower frequencies will most likely waste as much energy as outright rectification if at all possible.

    32. Re:Most important point not in summary by xded · · Score: 1

      You don't necessarily have to stack'em up. You could linearly change the single antenna lengths along the array, to let them resonate over different frequencies. This way you would obtain in a single layer a very wide bandwidth antenna. Or you could use other well-known RF tricks (assuming you're able to replicate them litographically).

      This would probably be one of the advantages over multi-junction solar cells. Of course assuming you're able to turn that HF energy into DC...

    33. Re:Most important point not in summary by Grog6 · · Score: 1

      You just need a really high frequency step-up transformer.

      One for each antenna... :)

      --
      Truth isn't Truth - Guliani
    34. Re:Most important point not in summary by c0lo · · Score: 1

      What are they using to rectify the signal to convert to DC? The antenna is neat - but not at all surprising, its size should just scale with wavelength. You could make a 125nm long antenna that would resonate with visible light (well withing the resolution of existing lithography). The problem is how to convert the 100THz signal you get to a DC signal. You need a fantastically fast diode.

      If they have managed this, that would be an impressive achievement.

      The PDF mentions (on page 2):

      One possible embodiment is metalinsulator-insulator-metal (MIIM) tunneling-diodes.

      Is it possible? Does it make sense?

      --
      Questions raise, answers kill. Raise questions to stay alive.
    35. Re:Most important point not in summary by Electricity+Likes+Me · · Score: 1

      The Carnot limit only applies to heat engines. It doesn't apply to electronics or electrochemical systems.

      So if you wrapped a Carnot engine in these, and added an electric motor booster to it's output, the system is no longer a Carnot engine, you've now got a hybrid (and can have much higher efficiency).

    36. Re:Most important point not in summary by Rei · · Score: 1

      That's because the input to an electric motor is low entropy (electricity), while the input to a heat engine is high entropy (heat). But here's the issue: the input to your total system is heat (the fuel for your engine). It doesn't matter how many "stages" or what kind of stages you add (aka, photovoltaic + electric, etc), you can't break Carnot's law for the closed system.

      --
      Could chocolate let me finish?
    37. Re:Most important point not in summary by Neil+Boekend · · Score: 1

      I do not think the 90+ efficiency is the greatest game changer. Since they claim it could be produced like a CD/DVD/BR the possibility to create very large surfaces with low costs is far more important IMHO. We have surface area enough, PV is just very expensive per watt. Of course, assuming the cost per m^2 stays the same, increasing the efficiency will help decreasing the cost per watt.
      The micro-antenna part seems feasible, but I do not know enough of quantum mechanics to asses the feasibility of the tunneling diodes. I have heard of them before, are they in (experimental) production? Do they reach these frequencies? Are they cheap enough to use one per antenna? Is it possible to create these in the same cheap way (with the CD/DVD/BR technology)?

      --
      Well, I might have a way, but it only works on a semi spherical planet in a vacuum.
    38. Re:Most important point not in summary by TheTurtlesMoves · · Score: 1

      I think you still don't quite get coherent in this context. For a femtosecond they may be 180 out of phase, then the next femtosecond its 129 deg since another photon with different phase is now also getting absorbed. Hence you just don't get a beat frequency. Each photon has a different and independent phase.

      --
      The Grey Goo disaster happened 3 billion years ago. This rock is covered in self replicating machines!
    39. Re:Most important point not in summary by Anonymous Coward · · Score: 0

      Nanoscale integrated vacuum microelectronics might be the way to make needle-shaped cathodes heated by the sunlight itself, if small enough 200THz would be possible. But not cheap, and part of the energy has to be turned into heat to make it work.

    40. Re:Most important point not in summary by BlackPignouf · · Score: 1

      Sorry, but that is utter bullshit.

      From TFA:

      "A theoretical efficiency of 92% was demonstrated at a peak resonance of 10um"

      Take a look at this graph : http://en.wikipedia.org/wiki/File:Solar_Spectrum.png
      10um (=10 000 nm) is not even on the graph. Why is that?
      First : the sun doesn't radiate that much around this wavelength. It corresponds to approximately 290K (~17C) black body radiation while the sun is at ~5800K. It is as much solar power as "human power" or "earth power" or "whatever in the neighboorhood power".
      Then: at this wavelength, the energy of every photon is 20 times less than those that are absorbed by usual solar cells.
      Which means that less than 0.1% of the solar radiation is available around this wavelength (see http://en.wikipedia.org/wiki/Planck's_law#Percentiles).

      If you integrate the efficiency curve multiplied by the spectral irradiance of the sun, you probably get less than 0.1%.
      Now, that's impressive for a theoretical efficiency! :D

    41. Re:Most important point not in summary by BlackPignouf · · Score: 1

      Yeah, too bad they're lying about the efficiency while conveniently ignoring thermodynamics.

    42. Re:Most important point not in summary by Anonymous Coward · · Score: 0

      The individual nantennas can absorb close to 90 percent of the available in-band energy.

      Perhaps some log periodic variant of nantenna is in order?

    43. Re:Most important point not in summary by Bengie · · Score: 1

      Cover the Earth with enough 90%+ efficient solar panels and watch the global temp drop, assuming enough power is stored or converted.

      Covering your house with those kinds of solar panels would not only reduce your house temp, but could power your AC.

    44. Re:Most important point not in summary by NikeHerc · · Score: 1

      For single frequency light, conventional solar cells can be quite efficient (~80%???)...

      If memory serves, quantum mechanical considerations limit solar cell efficiency to a much smaller number, possibly 18% to 23%.

      --
      Circle the wagons and fire inward. Entropy increases without bounds.
    45. Re:Most important point not in summary by CCarrot · · Score: 1

      I can't help but wonder about the entropy aspect. I mean, you're taking away blackbody radiation and turning it into power at extreme efficiency so that you can get work done all over again. Doesn't that strike anyone else as odd? I mean, let's say that you've got an engine near the Carnot limit and you wrapped it in these IR solar cells, which take 90% of the radiated waste heat and turn it into electricity, when you then use to power an electric motor to boost your engine's output. Would you not have just surpassed the Carnot limit?

      Sorry, had to do some quick reading on the Carnot limit. IANA Mech Eng, so my reasoning may be flawed...but here goes

      As far as I understand, the Carnot limit is tied to the input and output temperatures of the system. The larger the differential, the higher the theoretical efficiency of 'work' that can be produced by the system. If the solar cells are absorbing and utilizing the 'wasted' heat, aren't they in effect reducing the effective output heat for the engine? In which case, as I understand it, they would be driving up the Carnot limit at the same time, just in a two-stage process. If the recovered energy is then redirected back into the engine (tough, but possible I suppose), well, the effective Carnot limit of the system as a whole has been raised, so we're not breaking any theories of thermodynamics here.

      Apologies if I've completely missed the point. Mech and thermodynamics were always my worst classes ;o)

      --
      "I love animals! Some are cute, others are tasty, what's not to like?" - Betsy Schroeder, Jeopardy contestant
    46. Re:Most important point not in summary by KingBenny · · Score: 0

      does this mean we get to level 1 on the kardashev scale as soon as 15 years from now ???

      --
      Free speech was meant to be free for all... how can anyone grow up in a nanny state ?
  5. Re:Slow down and THINK before you use these. by Anonymous Coward · · Score: 1

    You lost me at "chiropractic doctor". No such thing, sorry guy.

  6. The biggest technical problem with the substrate by Anonymous Coward · · Score: 1

    Currently, they can only make these these things work with a flying car as the substrate.

  7. Rectification is the hard part by Anonymous Coward · · Score: 1

    Rectifier? Just sayin'. Can't run your stuff off of THz electricity.

    1. Re:Rectification is the hard part by Son+of+Byrne · · Score: 1

      Can't run your stuff off of THz electricity.

      Why not?

      I know I sound like a dolt, but maybe that's the game changing question?

      Anyone have any thoughts on why we can't "run our stuff off of THz electricity?"

      --
      I'd happily pay you Tuesday for a biopsy today!
    2. Re:Rectification is the hard part by Anonymous Coward · · Score: 0

      OK, sincere and possibly stupid question here; can't you run a pure resistance load of THz electricity?

      If so, you could maybe use this for solar thermal rather than photoelectric (!) - wire a bunch of these up to a resistance coil and drive a heat engine (steam turbine) off of that...

    3. Re:Rectification is the hard part by Anonymous Coward · · Score: 0

      Inductance and parasitic capacitance.

      Your THz electric signal is going to go everywhere except down the wire.

    4. Re:Rectification is the hard part by Anonymous Coward · · Score: 2, Insightful

      The simple answer is that electronics aren't instant. Every single wire and component in any device you can build actually acts like a resistor, capacitor, and inductor. The combination of these effects means that when you, say, apply a voltage to a wire, it takes some tiny amount of time to "charge up". Even with the gigahertz frequencies used in processors, things have to be specifically built (and be tiny) to work with these charge times. If you try and do anything with *terahertz* frequencies? Even a micrometer of wire won't be "charged' before the wave goes negative, at which point it discharges... and you wind up with an average of zero volts.

      TL;DR: Until we have wire made out of superconductor, frequencies that high simply can't be transfered through circuits.

    5. Re:Rectification is the hard part by vlm · · Score: 1

      Inductance and parasitic capacitance.

      Your THz electric signal is going to go everywhere except down the wire.

      The other problem is there really is nothing useful to do with THz AC.

      You can't really do anything "useful" with 60 Hz AC without rectifying it, or doing some AC motor stuff. I think it would take a rather large number of "poles" to make a three phase motor run off THz AC, and as you note, the inductance makes it unbuildable, so we won't be doing either the electric or the electronic thing.. leaving us with not much. Resistive heating?

      --
      "Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
    6. Re:Rectification is the hard part by Maddog+Batty · · Score: 1

      At the moment, the energy absorbed by the antenna isn't going anywhere as nobody has invented a suitable diode. It therefore will just end up as heat anyway.
      This isn't actually gaining you anything as a black sheet of paper will do this job equally as well.

      --
      wot no sig
    7. Re:Rectification is the hard part by Brett+Buck · · Score: 1

      Not a dolt but the capacitance and inductance of even a nice solid wire would prevent any current flow, suck it all up into heat in the first tiny fraction of an inch. Wire doesn't even work well for higher frequency radio waves, it's sure not going to work for this, which is many orders of magnitudes higher. And I would have to do some work on the topic and dig out my old solid-state physics book to know for sure, but I presume the things we consider conductors cease to be when the wavelength of the signal gets to be comparable to the distance between atoms in the lattice of the conductor.

    8. Re:Rectification is the hard part by Obfuscant · · Score: 1

      Even a micrometer of wire won't be "charged' before the wave goes negative, at which point it discharges... and you wind up with an average of zero volts.

      You always wind up with an average of zero volts when you use AC power. What you don't wind up with is zero volts RMS. RMS is a mathematical representation of the amount of work a power source can do -- designed so that 100 V RMS AC does the same work as 100 V DC.

    9. Re:Rectification is the hard part by Son+of+Byrne · · Score: 1

      Wire doesn't even work well for higher frequency radio waves

      Forgive my ignorance (again), but this leads me to wonder whether we just need to invent the equivalent of an optical motor (we obviously being someone smarter than me)?

      --
      I'd happily pay you Tuesday for a biopsy today!
    10. Re:Rectification is the hard part by Culture20 · · Score: 1

      You can't really do anything "useful" with 60 Hz AC without rectifying it, or doing some AC motor stuff. I think it would take a rather large number of "poles" to make a three phase motor run off THz AC, and as you note, the inductance makes it unbuildable, so we won't be doing either the electric or the electronic thing.. leaving us with not much. Resistive heating?

      And not over a long distance either. So IR input -> antenna -> extremely short distance THz AC -> IR output. At best, it's a cooling/heating film, radiating heat only on one side. At worst, it's the reverse of glass, transparent to IR, but opaque to the visible spectrum.

    11. Re:Rectification is the hard part by drerwk · · Score: 1

      Short answer is impedance mismatch. 60Hz has a wavelength of about 3000 miles, and you need a wire about that long to couple and cause radiative dissipation. When you get to THz, pretty much anything bigger than a gnat will now be an antenna. And there are other issue with conductivity being a function of frequency and so on.

  8. New use for ancient pattern? by Anonymous Coward · · Score: 0

    Greeks were way ahead of this with their "key pattern" motif. Who knew it would be useful in ways other than decorative when made microscopic and etched on a semiconductor substrate?

  9. body heat = infrared by dgatwood · · Score: 1

    Anybody else read this and immediately think that it might potentially solve the problem of biologically powering medical implants that was mentioned in a story on Slashdot about a week ago?

    --

    Check out my sci-fi/humor trilogy at PatriotsBooks.

    1. Re:body heat = infrared by Anonymous Coward · · Score: 0

      Nope just you so you better patent the idea!

    2. Re:body heat = infrared by dgatwood · · Score: 1

      By describing the invention here, at least it should count as publication of prior art in the field, should anyone else attempt to patent it in the future.

      --

      Check out my sci-fi/humor trilogy at PatriotsBooks.

  10. Beware by bananaquackmoo · · Score: 1, Informative

    Beware the PDF link

    1. Re:Beware by icebraining · · Score: 1

      I just use this to open them in Google Docs Viewer by default; it's all HTML to me.

  11. How hard can it be ... by Skapare · · Score: 1

    ... to etch an antenna at the wavelength of 0.000001 meter? Well, OK, it's not trivial. But we do have things like lasers that can etch chemicals at that size and smaller. Then we need a way to transfer that etch to conductive metal, add rectification to make it usable and collectible, and have our own little power sources. A flat panel might do if the current level doesn't burn up the collection tap point.

    --
    now we need to go OSS in diesel cars
    1. Re:How hard can it be ... by CCarrot · · Score: 1

      ... to etch an antenna at the wavelength of 0.000001 meter? Well, OK, it's not trivial. But we do have things like lasers that can etch chemicals at that size and smaller. Then we need a way to transfer that etch to conductive metal, add rectification to make it usable and collectible, and have our own little power sources. A flat panel might do if the current level doesn't burn up the collection tap point.

      They can 'print' them.
      https://inlportal.inl.gov/portal/server.pt?open=514&objID=1269&mode=2&featurestory=DA_101047

      This seems a bit well-aged for 'breaking' news, unless they've found some way to rectify the high frequency power...then it would be newsworthy indeed! I'll have to RTFA...

      --
      "I love animals! Some are cute, others are tasty, what's not to like?" - Betsy Schroeder, Jeopardy contestant
    2. Re:How hard can it be ... by chemicaldave · · Score: 3, Informative

      The newsworthiness is that instead of only 250 million nantennas on one small square like in that INL page, these guys replicated a design onto an "8 inch round silicon wafer" with 10 billion antenna elements. And they did it with high detail and little loss between the "master print" and the copy.

    3. Re:How hard can it be ... by CCarrot · · Score: 1

      Wow, that is quite impressive! I missed that in my skimming, thanks.

      Too bad we still can't do anything with all those antennas unless we can rectify the output...it seems like saying "look at how densely we can pack data into these drive platters!" before anybody has invented the read-write head. But it is good to know they're still trying to develop this idea.

      --
      "I love animals! Some are cute, others are tasty, what's not to like?" - Betsy Schroeder, Jeopardy contestant
    4. Re:How hard can it be ... by Bengie · · Score: 1

      Probably never had a real reason to have a diode that worked at 10thz. Now that there's a demand, a supply might pop up.

  12. huh wha? by sgt+scrub · · Score: 1

    so, does this mean they are making vibrators? i thought vibrators used electricity.

    --
    Having to work for a living is the root of all evil.
    1. Re:huh wha? by ceoyoyo · · Score: 1

      A vibrator uses an electric motor to convert electricity to motion. If instead, you impose motion, then the electric motor becomes a generator and produces electricity.

      Yes. Think that one through carefully. ;)

    2. Re:huh wha? by sgt+scrub · · Score: 1

      sorry. i was having a lexdysic moment

      --
      Having to work for a living is the root of all evil.
  13. Re:Slow down and THINK before you use these. by benjfowler · · Score: 1

    You're completely nuts.

  14. subluxations LOL by fyngyrz · · Score: 4, Funny

    Phrenologically speaking, your entire post is really lumpy. From a cooking standpoint, your pot is cracked. And scientifically speaking... well, why bring science into it now?

    --
    I've fallen off your lawn, and I can't get up.
  15. 2008? by Anonymous Coward · · Score: 0

    Did anyone else notice this paper was written in 2008? That means we are only 2-7 years away! I'll be powering my home with antennas that cover my roof in 2 short years!

    If this is such big news, why did it take 3 years to make it to /.?

  16. Re:Slow down and THINK before you use these. by Anonymous Coward · · Score: 0

    so polarized light can cause your vertebra to dislocate? how? what happens when I wear my polarized sunglasses? sounds like a quack making money from speaking engagements.

  17. Nothing new by Maximum+Prophet · · Score: 2

    Don Lancaster described this process years ago. The trick is the tiny diode at the bottom of the antenna to turn the AC into DC. It has to handle 400 - 800 THz. Plausible, but difficult. 5-10 years really means they have no idea when they'd be able to produce this in industrial quantities.

    --
    All ideas^H^H^H^H^Hprocesses in this post are Patent Pending. (as well as the process of patenting all postings)
  18. Is this a very old idea by Anonymous Coward · · Score: 1

    When Tesla was determining the resonant frequencies of the earth to potentially transmit unlimited electric power, he also recognized frequencies that acted as a damping field to nullify electric power. With the advent of the wireless and Tesla's unique investigations into broadcasting electricity, a dozen or more inventors thereafter announced their own means for transmitting electrical energy without wires. One British inventor, H. Grindell-Matthews, actually demonstrated his "mystery ray" apparatus in 1924 to a Popular Science Monthly writer in London (See: Pop. Sci. Monthly, Aug. 1924, P. 33). When his beam was directed toward the magneto system of a gasoline engine, it stopped the system. Afterwards, it ignited gun powder, lit an electric lamp bulb from a distance and killed a mouse in seconds! Grindell-Matthews said the secret was involved with the "carrier beam" he used to conduct a high-voltage, low-frequency electrical current. During 1936, Guglielmo Marconi experimented with extremely low frequency (ELF) waves and displayed their exceptional ability to penetrate metallic shielding. These waves could affect electrical devices, overload circuits and cause machines like generators, electric motors and automobiles to stall. Diesel engines, which do not rely on electrical ignition, were not affected. Mysteriously, Marconi's research on the subject was never found after the war.

    1. Re:Is this a very old idea by bmo · · Score: 2

      Amiga fanboys come in second only to Tesla fanboys.

      It's 2011.

      Tesla's dead.

      --
      BMO

  19. Re:Slow down and THINK before you use these. by Anonymous Coward · · Score: 0

    I thought you might be telling a joke with a straight face.
    Then I came to the part about the presenter being "a well respected chiropractic doctor" and I knew that was indeed the case. You're funny.

  20. Re:Slow down and THINK before you use these. by Brett+Buck · · Score: 1

    . These micro antennae will effectively absorb midrange IR light and reflect everything else back out as polarized light minus the IR. This is sure to cause skin cancer, retinal damage and other maladies.

        You mean that it will spew more UV and other light out than went into it? Making it worse than the same exposure without absorbing the IR?

          Go ask your medical school for your money back, *quick*, because even a doctor should understand the fundamentals of thermodynamics.

  21. Re:Slow down and THINK before you use these. by Anonymous Coward · · Score: 0

    I don't think you have any Idea what you're talking about.

    You seem to be of the opinion that the presence of these antennae are removing the IR from light that doesn't strike them (which is idiotic). You also seem to be poorly isolating variables and correlations with your attribution of a causal relationship between polarized light and "vertebral subluxations". Did you realize that the light from most modern computer monitors and a sigifigant portion of natural light is polarized?

  22. Re:Slow down and THINK before you use these. by Anonymous Coward · · Score: 1

    ALL smooth reflective surfaces reflect mostly-polarized light, dipshit. That's why polarizing sunglasses work.

  23. Re:Slow down and THINK before you use these. by Gogogoch · · Score: 1

    hahaha

  24. Patent the Inevntion! by Anonymous Coward · · Score: 0

    Someone made a new break thru invention and they should quickly patent it!
    Never mind, patents are useless because no one invents anything by themselves any more.

  25. Re:Slow down and THINK before you use these. by Anonymous Coward · · Score: 1


    Go ask your medical school for your money back, *quick*, because even a doctor should understand the fundamentals of thermodynamics

    The vast majority (all?) "Doctors of Chiropractic" have never attended medical school. They go to chiropractic colleges which bestow the academic title of "Doctor" on them. Don't be fooled, they are not medical doctors.

  26. Re:Slow down and THINK before you use these. by doti · · Score: 1

    but not a well respected chiropractic doctor

    --
    factor 966971: 966971
  27. Re:Slow down and THINK before you use these. by slackzilly · · Score: 1

    What does micro-subluxations have to do with polarized light?

    If you sit in a movie theater seat for two hours without polarized light I am pretty sure you will experience the same effect.

    --
    - "If one man can create that much hate, you can only imagine how much love we as a togetherness can create."
  28. Re:Slow down and THINK before you use these. by mldi · · Score: 1, Informative

    Doctor of Chiropractic (DC) are indeed doctors. http://en.wikipedia.org/wiki/Chiropractic_education

    But not medical doctors. Considering the subject at hand was medical, all reputation is out the window.

    --
    If you aren't suspicious of your government's actions, you aren't doing your job as a responsible citizen.
  29. Re:Slow down and THINK before you use these. by Fjandr · · Score: 1, Informative

    Yup, the correct term is "Doctor of Chiropractic," though I'm sure that's not what you actually meant.

    No, it's not an MD. The term "doctor" is fairly general, and used in a wide manner to mean people other than those who can prescribe controlled substances or perform surgery.

  30. Thermodynamics is a bitch. by Anonymous Coward · · Score: 2, Insightful

    This is, of course, utterly useless for harvesting power from ambient thermal radiation. Even if you can make a diode that's remotely capable of rectifying current at high enough frequencies, the diode has to be kept colder than the source of the radiation. It's the electrical analog of a Brownian ratchet.

    Picking up a bit of the IR tail that conventional photovoltaics don't catch? Maybe, but there isn't very much power down there even if you got the efficiency usefully high. Turning ambient heat into usable energy? Sorry, no.

  31. Re:Slow down and THINK before you use these. by GameboyRMH · · Score: 2

    Parent is successfully trolling the shit out of everyone.

    --
    "When information is power, privacy is freedom" - Jah-Wren Ryel
  32. nano devices for rectification by si3n4 · · Score: 1

    http://personalpages.manchester.ac.uk/staff/A.Song/research/BallisticRectifier.htm this is the only link I could find , I saw this topic some time ago - the ability to build nano structures may solve the rectification - I am sure there was another paper with a different device configuration but I'll never find the thread now - doesn't make this tomorrow but it means a lead on both ends

    1. Re:nano devices for rectification by Anonymous Coward · · Score: 0

      That "classical" diagram just made me more confused. What happens to the electrons coming in the top? They have to go some where or you'd just build up a static charge and the field would stop any new electrons. A few searches and I found some real research papers. These devices need to be very cold (77K).

  33. Re:Slow down and THINK before you use these. by retchdog · · Score: 1

    the "lux" part, i guess. :-/

    --
    "They were pure niggers." – Noam Chomsky
  34. Re:Slow down and THINK before you use these. by NeutronCowboy · · Score: 1

    A classic troll. Well done.

    --
    Those who can, do. Those who can't, sue.
  35. Re:Slow down and THINK before you use these. by Anonymous Coward · · Score: 0

    Did you know that those subluxuations you're talking about, the core tenets of chiropractics, are bullshit? You even debate amongst yourself about what the fuck they are.

    These vertebral subluxuations, if you chiropractors could agree on what they are, have nothing to do with any illness and treating them does nothing.

    Your living in a make-believe castle made out of bullshit. Wake up. Pick a new world view that isn't based on lies.

  36. Caveats by killmenow · · Score: 0

    The usual caveat applies: it may be 5-10 years until this could hit the market.

    The solar constant caveat applies: it will always be 5-10 years until this could hit the market.

    ALWAYS.

  37. Re:Slow down and THINK before you use these. by Anonymous Coward · · Score: 0

    Calling yourself doctor does not make you a doctor. Just like dentists. Either do a PhD, or try the 10,000 hours of medical school or 8000 hours of law school if you want to be a real "doctor".

  38. The problem with solar power by gilesjuk · · Score: 1

    This is the problem with solar power, it's mostly home owners who are buying them and the systems cost so much it takes decades to break even (if purely doing it for cost reasons, not CO2).

    So once a better technology comes along you have to junk the old tech and you may never break even.

    1. Re:The problem with solar power by Em+Adespoton · · Score: 2

      This is the problem with solar power, it's mostly home owners who are buying them and the systems cost so much it takes decades to break even (if purely doing it for cost reasons, not CO2).

      So once a better technology comes along you have to junk the old tech and you may never break even.

      Hello 1978, welcome to 2011 where panels pay for themselves within 4 years, have a lifespan of 20+ years, and are significantly cheaper to produce and use less-rare components.

    2. Re:The problem with solar power by Anonymous Coward · · Score: 0

      As a former horse and buggy owner and current owner of an android phone, I agree with your sentiments.

    3. Re:The problem with solar power by CrimsonAvenger · · Score: 1

      panels pay for themselves within 4 years

      You forgot to mention the tax credits and subsidies that make that four year timetable possible.

      Which means that as long as only a very few people install them, they're cheap. If EVERYONE installed them, well, the tax credits would basically reduce to "you pay for your neighbor's solar panels, and he'll pay for your solar panels"....

      --

      "I do not agree with what you say, but I will defend to the death your right to say it"
    4. Re:The problem with solar power by ptbarnett · · Score: 1

      Hello 1978, welcome to 2011 where panels pay for themselves within 4 years, have a lifespan of 20+ years, and are significantly cheaper to produce and use less-rare components.

      Maybe where you live. But, where I live, I'm paying 9.5 cents per kWh, and averaging about 1000 kWh per month. The present value (at a 4.5% discount rate) of my electric bill over 20 years at that price and consumption rate is about $15,000. Of course, I can't count on my electric rate remaining at 9.5 cents per kWh. I was paying almost twice that a few years ago.

      A quick search of the net finds a calculator that says the average sun-hours per day in my area is 5.43, and I'd need 7.4 kW of solar panels to generate enough electricity for a zero net consumption (presuming net metering, rather than storing it locally). I'm not aware of any solar panel systems that sell for $2.00 per watt, installed

      To break even in 4 years as you claim, the cost would have to drop to a bit more than $4,000, or about 57 cents/watt, installed. Where do I find these solar panels?

    5. Re:The problem with solar power by Ungrounded+Lightning · · Score: 1

      Maybe where you live. But, where I live, I'm paying 9.5 cents per kWh, ... To break even in 4 years as you claim, the cost would have to drop to a bit more than $4,000, or about 57 cents/watt, installed. Where do I find these solar panels?

      Panel prices have been dropping but they're not quite that low yet. There's a company in Florida that sells UL approved panels for about $2/watt and non-approved for about $1. (It changes from time to time. I get the impression they're selling cosmetic rejects from major manufacturers.)

      Solar panels have been beyond price break-even for new construction in rural areas (where it can cost tens of thousands of dollars to put in grid power) for some years. Also for small stuff (yard lights, emergency phones, illuminated road signs, some billboards) where the load is small enough that the solar power system is cheaper than running grid power even though the grid is handy.

      A dollar a watt for panels is about where solar becomes practical for houses in sunny suburban areas at current California progressive/socialized electric rates. (Note that it's not just the cost of the panels you have to amortize. You also need storage, an inverter, etc. Using the grid rather than batteries as "storage" means a much pricier inverter and more pricey red tape, while batteries need periodic replacement, and ongoing cost.)

      --
      Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
    6. Re:The problem with solar power by ningaui · · Score: 1

      This is the problem with solar power, it's mostly home owners who are buying them and the systems cost so much it takes decades to break even (if purely doing it for cost reasons, not CO2).

      So once a better technology comes along you have to junk the old tech and you may never break even.

      As others have suggested, that depends on where you live, how much you pay for electricity, how much the panels cost, whether the electricity company pays you for electricity you export to the grid, and so on.

      We've just had solar panels installed on the office (in Australia), after a lot of research and number crunching. Break even is less than 5 years. Panels are guaranteed for 25 years, and expected to last up to 40 years. The inverter will probably need to be replaced in maybe 15 years, but by then they should be pretty cheap. Projection is that the electricity company will pay us about $500 over the first 12 months, for the energy we export to the grid. We don't expect any electricity bills for at least 10 years (maybe 20, depends on inflation etc assumptions), and even then the bills will be for part of the "supply charge". The company that did the install mostly does large installs on commercial/educational/etc buildings, and they are flat out.

      So your comments may be true for where you live, but there are plenty of places where it does make sense to install solar power now. And a lot of people aren't even considering it, because they've heard someone say that it takes decades to break even, and they don't realise that may not apply to them.

      Because so many people are installing solar here, prices are coming down rapidly. I read a little while ago that panel prices have dropped by half since 2009. So if you're interested in maybe installing solar, I suggest you look into it. If it isn't right for you at the moment, wait 3 or 4 years and look into it again.

    7. Re:The problem with solar power by Maxo-Texas · · Score: 1

      Two other factors

      * If you don't shoot for complete replacement, you can generate about $50 per month of power with a $4000 system (~250kwh/month). Then- in the summer, when you hit the penalty power rates, you are generating $75 per month of power. So about $700 per year.

      Where in the market can you invest $4000 and get a safe $700 payout?

      But that's $700 *savings*. Which means it's tax free. Which means it's like earning $1000 from investments (or $1250 more in salary).

      And power rates have roughly doubled since 1985 (5c/kwh back then except for wierd things like Hydroelectric)

      --
      She was like chocolate when she drank... semi-sweet at first and then increasingly bitter.
    8. Re:The problem with solar power by Anonymous Coward · · Score: 0

      4 years?
       
      My parents just got 4KW of panels installed and are looking at 10-15 years at least before the cost is recouped.

  39. Re:Slow down and THINK before you use these. by Dunbal · · Score: 1

    They are, however, masters at getting the gullible to part with their money.

    --
    Seven puppies were harmed during the making of this post.
  40. Unobtainum diodes by Animats · · Score: 4, Informative

    What are they using to rectify the signal to convert to DC?

    Unobtainum diodes. They don't actually know how to do that.

    Terahertz diodes do exist. Low-cost, high-efficiency, integrated terahertz diodes, no. But as work proceeds on terahertz electronics, someone may solve that problem. Each nanoantenna needs its own nanodiode, so the diodes have to be fabricated on the substrate with the antenna, which complicates the fab problem. The enthusiasm about roll-to-roll low cost fabrication in the article is premature. We'll probably see this working first on a wafer, and it may not be cheap.

    Even if it's expensive, there's an initial market for satellite power panels. The performance improvement would be worth it.

    1. Re:Unobtainum diodes by joe_frisch · · Score: 5, Informative

      I've bought some 300Ghz diodes from Virginia Diodes. Worked great, but $7K each as I remember......

      Here they need more like 100 THz. Might be possible with some sort of nonlinear optical material, but the fields are probably much too low.

      Even if this whole scheme does work, its not clear it is any better than a conventional solar cell - they are quite efficient for narrow-band radiation right above their bandgap. You can stack different band-gap solar cells to get a quite efficient stack, but it doesn't make economic sense - sunlight is free, its the solar cells that cost money......

    2. Re:Unobtainum diodes by Intrepid+imaginaut · · Score: 2

      its not clear it is any better than a conventional solar cell

      Working at night is a decent beneift.

    3. Re:Unobtainum diodes by wierd_w · · Score: 1

      An odd idea just occured to me...

      Perhaps you dont need to switch at that frequency.

      If you have two antennas of very close lengths, but sufficiently different in length to resonate at different discrete frequencies, you could combine them to produce a very reliable "Beat" wave of a much lower frequency that would have partial wave reinforcement from both antennas, that would be within the capabilities of current transisto technology.

      Naturally this would sacrifice a huge amount of the potential energy of the waves you are trying to harvest, but it might make this technology buildable and testable in a shorter period of time, thus preventing it from dieing on the vine while waiting for faster silicon (or equivilent.)

    4. Re:Unobtainum diodes by joe_frisch · · Score: 2

      Unfortunately unless you combine in a nonlinear device, the beat just has the original frequency components. If you were to combine the 2 signals in a linear circuit and then low pass filter, you wouldn't see anything. A nonlinear combination would produce a low frequency signal - this technique is called "mixing" and is very widely used in radio systems. The mixer that does the nonlinear combination is typically constructed from a set of diodes - so you wind up back with the original problem.

    5. Re:Unobtainum diodes by avandesande · · Score: 1

      Antenna would probably work at a much higher temperature than semiconductors so it might be possible to focus the light on a small area.

      --
      love is just extroverted narcissism
    6. Re:Unobtainum diodes by Anonymous Coward · · Score: 0

      >> Each nanoantenna needs its own nanodiode, so the diodes have to be fabricated on the substrate with the antenna,
      >> which complicates the fab problem.

      Not necessarily... You could fab an array of phased elements, and only have a diode at one end of the array.

      Just Sayin'...

    7. Re:Unobtainum diodes by Anonymous Coward · · Score: 0

      I've bought some 300Ghz diodes from Virginia Diodes. Worked great, but $7K each as I remember......

      What did you do that required multiple $7K diodes?

    8. Re:Unobtainum diodes by Neil+Boekend · · Score: 1

      That will only work if the signals to each antenna are in phase. The phase in sunlight shifts all over the place so you can't build a phased array. You do need a rectifier for each antenna.
      Normal phased arrays are used in conjunction with a single transmitter, which sends it's signal in one phase. The sun isn't one transmitter, it's as many transmitters as there are atoms on the visible surface, each with it's own phase...

      --
      Well, I might have a way, but it only works on a semi spherical planet in a vacuum.
    9. Re:Unobtainum diodes by ultranova · · Score: 1

      Working at night is a decent beneift.

      Yeah, it does so by converting ambient infrared radiation - in other words, ambient heat - into work. Any waste heat released through said work is then re-absorbed by the antenna, to be used again.

      In other words, this sounds like a second-order perpetual motion machine to me.

      --

      Forget magic. Any technology distinguishable from divine power is insufficiently advanced.

    10. Re:Unobtainum diodes by TheTurtlesMoves · · Score: 1

      Also as noted above. The input is not coherent, so even with a mixer you still would not get a beat frequency.

      --
      The Grey Goo disaster happened 3 billion years ago. This rock is covered in self replicating machines!
    11. Re:Unobtainum diodes by Anonymous Coward · · Score: 0

      They need to develop a biological solution to the rectification problem, it will be cheap to mass produce in this case and the raw materials will be orders of magnitude more abundant than with an inorganic solution.

    12. Re:Unobtainum diodes by Anonymous Coward · · Score: 0

      If he tells you, I'd have to kill you.

  41. Ressonance good for communication not power by erice · · Score: 2

    The individual nantennas can absorb close to 90 percent of the available in-band energy.

    Which is good for communications, where you want to exclude all but the target band. It could even work for power, providing the light source is a laser. But resonance methods aren't very good for capturing energy from broad spectrum sources like the sun.

    I predict that this technique will never gain traction for solar energy. However, it might replace photodiodes for fiber optic communications.

    1. Re:Ressonance good for communication not power by wagnerrp · · Score: 1

      MASERs and rectenna already operate using this same principle, and similarly operate at 85% or better efficiency. Since they operate in the tens of GHz range, there are readily available electronics available to handle them.

    2. Re:Ressonance good for communication not power by demonbug · · Score: 3, Funny

      MASERs and rectenna already operate using this same principle, and similarly operate at 85% or better efficiency. Since they operate in the tens of GHz range, there are readily available electronics available to handle them.

      Cartman had one of those, right?

    3. Re:Ressonance good for communication not power by wagnerrp · · Score: 2

      I think that would be a rectish.

    4. Re:Ressonance good for communication not power by im_thatoneguy · · Score: 1

      Could have useful applications I guess also for space based solar power. Perhaps a space based laser and ground based exceedingly expensive photo-antenna.

  42. Yawn by wcrowe · · Score: 1

    Yeah, I'm still waiting on the amazing solar innovations that were breathlessly announced five years ago to hit the market.

    --
    Proverbs 21:19
    1. Re:Yawn by demonbug · · Score: 1

      Yeah, I'm still waiting on the amazing solar innovations that were breathlessly announced five years ago to hit the market.

      I was going to try looking up some solar power articles from five years ago, but there doesn't seem to be an easy way to restrict a search to a particular time period. Is there an advanced Slashdot search hidden away somewhere? Even Google only lets me restrict my search to "past day" or "past year", etc. I could have sworn you used to be able to actually input a date range, but it isn't there any more.

    2. Re:Yawn by vonux · · Score: 1

      Maybe I'm just lucky, but Google let's me define a custom range.

  43. like dog years, but rather... by arikol · · Score: 1

    Is this 5-10 flying car years? Similar to dog years but in the other direction. 1 flying car year equals 1 normal human lifespan, apparently...

  44. Re:Slow down and THINK before you use these. by Anonymous Coward · · Score: 1

    Doctor of Chiropractic (DC) are indeed doctors.

    Nope, you're quacks. You're actually more dangerous than most quacks in the placebo business, because some of you quacks break people's necks and spines.

  45. Re:Slow down and THINK before you use these. by slackzilly · · Score: 1

    You didn't google the word subluxations did you.

    --
    - "If one man can create that much hate, you can only imagine how much love we as a togetherness can create."
  46. Re:Slow down and THINK before you use these. by Skidborg · · Score: 1

    You do realize that he posts almost this exact same post on every few threads merely to generate responses like yours?

    --
    Supporter of the +1 Over Dramatic mod option. In memory of apk.
  47. Anti-global warming? by hansraj · · Score: 1

    Is it possible that a widespread use of such antennas will lower the average temperature since it is tuned to mid range infra-red? They can sell it being super eco friendly :-)

    1. Re:Anti-global warming? by hansraj · · Score: 1

      'sell it (to target audience) as being.."

    2. Re:Anti-global warming? by slinches · · Score: 1

      No.

      At least not unless tiny wires can somehow invalidate the conservation of energy.

      --
      Knowledge Brings Fear
  48. Brilliant by rabtech · · Score: 1

    Summary: They designed nano-scale devices that behave as antennas at infrared frequencies, meaning that infrared light induces a THz current in the antenna. They then proceeded to manufacture a few one-off test pieces that performed well and are now using a master pattern to roll/stamp the devices onto a film (though the full results of that weren't shown or aren't known yet).

    We don't typically think of stuff like light as being susceptible to this sort of thing because we haven't been able to make the antennas small enough to work at those wavelengths. In theory the technique can be used to design antennas that capture any part of the electromagnetic spectrum.

    The key piece they are missing is cheap efficient THz rectifiers that can convert the induced AC current into usable DC voltages. Not a small problem but not an impossible one either.

    --
    Natural != (nontoxic || beneficial)
  49. Re:Slow down and THINK before you use these. by Profane+MuthaFucka · · Score: 1

    Well you might as well get a fucking Doctorate of Unicornology and be much more useful to society.

    --
    Fascism trolls keeping me up every night. When I starts a preachin', he HITS ME WITH HIS REICH!
  50. Re:Slow down and THINK before you use these. by Brett+Buck · · Score: 1

    Ah,missed the "DC". I think I will go get an adjustment to cure my appendicitis...

  51. Re:Slow down and THINK before you use these. by retchdog · · Score: 1

    no, i didn't need to. what's your point here, exactly? if you didn't get the pun, then feel free to die in a fire.

    --
    "They were pure niggers." – Noam Chomsky
  52. Not new technology by Anonymous Coward · · Score: 0

    Similar tech has been used on the last few generations of Keyhole birds. They solved the rectification problem by doing everything analog and analyzing the interference patterns (at a much more reasonable speed). Still used some pretty nasty GaAs circuits though...

    I'd expect something useful (besides satellite imaging) could be done with a huge array of these.

    AC for obvious reasons.

  53. Violation of the second law of thermodynamics? by Michael+Woodhams · · Score: 1

    From the summary "The antennae are tuned towards midrange infrared light (5-10 um), which is abundant on our cozy-warm Earth â" even at night."

    But you can't extract work from a system which is in thermal equilibrium. This can't work unless the 'solar panels' are colder than the ambient night time radiation, which seems unlikely.

    I couldn't read TFA (slashdotted?), I skim read the fine paper, but didn't find any reference to this idea. So has someone incorrectly introduced this idea somewhere between the paper and the slashdot summary, or am I missing something?

    --
    Quattuor res in hoc mundo sanctae sunt: libri, liberi, libertas et liberalitas.
    1. Re:Violation of the second law of thermodynamics? by Dynetrekk · · Score: 1

      You, sir, are correct. Einstein was asked which physics theories he thought would stand the test of time, and he listed thermodynamics and general relativity, because they are so general. I'm with Einstein on this one. Oh, and IAAP, by the way.

    2. Re:Violation of the second law of thermodynamics? by barv · · Score: 1

      yes. violation. so few notice. puts me off slashdot.

    3. Re:Violation of the second law of thermodynamics? by Bengie · · Score: 1

      I'm no physics major of any sort, but when you say "system in thermal equilibrium", you mean of actual heat. Yes, no heat transfer should be happening conductivity. But there is a radiation heat transfer going on. With conductive heat, if the two bodies are the same temp, there's no physical heat flow, but with IR, there is radiative heat flow all the time. Even if the system is in balance, there is still IR radiation flowing. They're just tapping into that.

      So long as there's IR photons moving, heat is moving.

      At least this is my understanding, which could very well be wrong.

  54. Rectifier? by Anonymous Coward · · Score: 0

    Darn near killed her!

  55. Re:Slow down and THINK before you use these. by DurendalMac · · Score: 1

    I can't tell if this guy is a really dedicated troll (look at his history) or just a complete and utter lunatic who bases his shit off of some of the most ludicrous junk science out there. Either way, it's a really, really sad thing to see.

  56. Re:Slow down and THINK before you use these. by benjfowler · · Score: 1

    Over my head... I don't see any telltale signs that GP is any different from any random nutter on the Internet.

  57. Newsworthiness would HAVE to be fabrication detail by Ungrounded+Lightning · · Score: 1

    The newsworthiness is that instead of only 250 million nantennas on one small square like in that INL page, these guys replicated a design onto an "8 inch round silicon wafer" with 10 billion antenna elements. And they did it with high detail and little loss between the "master print" and the copy.

    The newsworthiness would HAVE to be in the fabrication and design details. "Optical rectennas" as a form of solar cell have been discussed since AT LEAST the late 1980s (when I heard them described by other people in the L5 society.)

    --
    Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
  58. Optical Rectenna 2.0 by The+Master+Control+P · · Score: 1

    This is basically a reprisal of the optical rectenna, and it's already been pointed out that the hardest part isn't rectifying THz radiation, which requires only nanolithiography-sized antennae, but creating the diode fast enough to turn it into DC.

    The above link details the status of optical rectennas as of roughly 2002; They managed to get an efficiency of 1% in the near-infrared (100THz) - the diode just didn't exhibit the asymmetry and nonlinearity needed. I'd bet that to make anything happen efficiently at optical speeds, they'll have to somehow create a diode that's based on atomic behavior rather than the bulk electron fluid.

  59. Bug antennae by Ungrounded+Lightning · · Score: 3, Informative

    Antennae are for bugs.

    Funny you should mention that.

    Apparently insects have similar antenna systems in their antennae to detect pheromones by their infrared signature. Also electret excitation structures attached other antenna structures to emit tuned infrared when pumped by grooming.

    Here's one reference.

    --
    Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
    1. Re:Bug antennae by pepax · · Score: 1

      Well, that paper came out in 1975, before the era of molecular biology, back when people knew almost nothing about how the sense of smell, or pheromone detection worked. In 1991 Buck and Axel published their paper in Cell on discovery of odorant receptor proteins (in mouse), which then led to discovery of odorant receptor proteins in insects, and other receptor protein families (V1R, V2R, TAAR) that are likely responsible for pheromone detection in mammals, and yet more receptor proteins likely responsible for pheromone detection in insects. Buck and Axel received a Nobel prize for their discovery. Btw., a 'vibrational theory of olfaction', similar to what you cite, popularized by the book The Emperor of Scent (Random House, 2002) was thoroughly destroyed by Leslie Vosshall's research published in 2004 in Nature Neuroscience.

    2. Re:Bug antennae by Ungrounded+Lightning · · Score: 1

      Well, that paper came out in 1975, before the era of molecular biology, back when people knew almost nothing about how the sense of smell, or pheromone detection worked.

      Thanks.

      The chemical "lock and key" theory had been around - and dominant - far before that, even if the "locks", "keys", and related signaling chains had not been identified.

      Btw., a 'vibrational theory of olfaction', similar to what you cite, popularized by the book The Emperor of Scent (Random House, 2002) was thoroughly destroyed by Leslie Vosshall's research published in 2004 in Nature Neuroscience.

      And I presume it also demolished Thomas Dykstra's 1994-1997 work.

      Thanks for the correction. (I found the "infrared signature of pheromones" theory, but not its refutation, when hunting down the stuff on the log-periodic antenna-like structures I'd run into previously. Should have looked further, with such a flakey-sounding use for an infrared "radio" )

      But that still leaves open the question of whether these structures, which seems clearly optimal for the purpose, ARE involved in electromagnetic wave detection, emission, and/or modulation (even if it's not for the detection of chemicals floating on the wind.) While structures so optimal for focusing electromagnetic waves might have been accidental fallout of some OTHER factor, would be easier to explain their pervasiveness if they actually DID have something to do with hacking EM waves.

      Sensitive and directional detection of infrared would certainly be useful to, for instance, a flying insect: Avoidance of bats and detection of a potential mate's body heat are two uses that come to mind. And if both detection and modulated emission is possible using these structures you've got a "radio link" suitable both for communication between, and direction finding of, other members of the species. No "molecular infrared signature" required.

      --
      Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
  60. Re:Slow down and THINK before you use these. by NeutronCowboy · · Score: 1

    Precisely. The hall mark of a good troll is that the poster hits many of the arguments that make people jump, with just enough hints to indicate that it isn't an authentic nutter.

    --
    Those who can, do. Those who can't, sue.
  61. Old news? by ridgecritter · · Score: 1

    Collecting solar energy with antennas - LLL seems to have done this in 2007.

    https://inlportal.inl.gov/portal/server.pt?open=514&objID=1269&mode=2&featurestory=DA_101047

  62. Re:Slow down and THINK before you use these. by mug+funky · · Score: 1

    successful troll is successful!

    bravo!

    excuse me while i get wasted on some water with the memory of hard liquor imprinted in it.

  63. Non-coherence can be a problem? by Anonymous Coward · · Score: 0

    I wonder if the non-coherent nature of the sunlight is going to be a problem as each antenna is going to be washed over by a superposition of out-of-phase waves.

  64. The rectification problem by Anonymous Coward · · Score: 0

    Field emission vacuum diodes might get there. I seem to recollect that diamond can have a zero or negative work function.

  65. Sorry, obeying the laws of thermodynamics ... by Ihlosi · · Score: 1

    ... is mandatory, and the laws after the first are by no means optional.

  66. Heinlein saw this by MichaelSmith · · Score: 1

    He used the idea of using a kind of radio receiver to collect solar energy in several of his short stories, including The Roads Must Roll

  67. What about the reverse? by Anonymous Coward · · Score: 0

    Could they use these miniature antennas to emit light? A 80% efficiency light bulb would be a game-changer.

    1. Re:What about the reverse? by Darkfred · · Score: 1

      um wouldn't that just be an LED?

      --
      ----- 70% of all statistics are completely made up.
  68. Re:Slow down and THINK before you use these. by fredmosby · · Score: 1

    Homeopathic alcohol would be an interesting product to see in an organic food store. Of coarse according to homeopathy it would 'cure' drunkenness.

  69. Invented in 1972: Link to survey of previous work by Ungrounded+Lightning · · Score: 1

    "Optical rectennas" as a form of solar cell have been discussed since AT LEAST the late 1980s (when I heard them described by other people in the L5 society.

    Apparently it was originally proposed in 1972 by Robert Baley.
    Here's a link to a 2004 survey of previous work.

    --
    Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
  70. Make that "proposed in 1972" by Ungrounded+Lightning · · Score: 1

    Invented in 1972: Link to survey of previous work

    Make that "proposed in 1972".

    As fabrication technologies improved since, various ways to actually do it, or do parts of it (of which this is the latest), have been invented.

    This one seems to be a new family of antenna array and interconnect structures without any new work on the underlying rectification mechanism.

    --
    Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
  71. Re:Slow down and THINK before you use these. by damn_registrars · · Score: 1

    Doctor of Chiropractic (DC) are indeed doctors.

    Only in America do we bestow the honor of "doctor" upon those who never wrote a dissertation. The rest of the world recognizes the inaccuracy of calling someone who went through chiropractor, medical, dental, veterinary, or law school a "doctor".

    Nobody who has not written and defended a research dissertation should go around advertising themselves a "doctor".

    --
    Damn_registrars has no butt-hole. Damn_registrars has no use for a butt-hole.