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After 60 Years, a Room-Temperature Maser

gbrumfiel writes "Before there were lasers, there were masers: systems that amplified microwaves instead of light. Solid state masers are used in a variety of applications, including deep space communication, but they've never been as popular as lasers, in part because they have to be cooled to near absolute zero in order to work. Now a team of British physicists have built a room-temperature maser using some spare chemicals and a laser they bought off of eBay. The new device is 100 million times as powerful as existing masers and might revolutionize telecommunications."

102 comments

  1. revolutionize eh? by Anonymous Coward · · Score: 0

    then give it out freely and let man really use it wickedly

    1. Re:revolutionize eh? by Anonymous Coward · · Score: 0

      Not every evil scientist. Some of us make do with regular masers attached to freezerays.

    2. Re:revolutionize eh? by Anonymous Coward · · Score: 0

      Now those in turn could be attached to the heads of polar bears!

    3. Re:revolutionize eh? by Anonymous Coward · · Score: 1

      It's not a death ray or an ice beam - that's all Johnny Snow.

  2. pffff! by cynop · · Score: 0

    ...let me know when they make a working room-temperature faser.

  3. Staff Weapon! by Anonymous Coward · · Score: 0

    Does this mean I can have my very own Goa'uld staff weapon yet?

    1. Re:Staff Weapon! by lister+king+of+smeg · · Score: 1, Insightful

      i'd rather have a zat'nik'tel

      --
      ---Saying gnome 3 is better than windows 8 not so much a compliment as it is damning with light praise.
  4. Not the first room temperature maser by Anonymous Coward · · Score: 1

    While this may be the worlds' first room-temperature solid-state maser, it certainly isn't the first room temperature maser. Standard hydrogen masers (the ones that help NIST tell what time it is) are certainly not cryogenic.

    1. Re:Not the first room temperature maser by game+kid · · Score: 2

      Ah, but does that use a laser they bought off of eBay?

      No? Then *yawn*.

      I mean, just imagine what the British team can do with a laser they bought off of craigslist or backpage.

      --
      You can hold down the "B" button for continuous firing.
    2. Re:Not the first room temperature maser by teridon · · Score: 1

      Can hydrogen masers amplify any frequency? I admit I know next to nothing about them, but I was under the impression they could only amplify at the resonant frequency of hydrogen (e.g. see http://tf.nist.gov/general/enc-h.htm)?

      --
      I hold it, that a little rebellion, now and then, is a good thing. -- Thomas Jefferson
    3. Re:Not the first room temperature maser by Anonymous Coward · · Score: 0

      Well, a rubidium maser can produce signal at different frequencies. I'm sure that there are masers that use other transitions as well.

  5. Re:Cold Fusion? by cjc25 · · Score: 5, Informative

    Because you saw the words "room-temperature" and you missed the last sentence of the first paragraph where it says the findings were published in one of the most widely respected peer reviewed journals?

    Or just didn't read TFA ;)

  6. Absolute Zero by Anonymous Coward · · Score: 5, Insightful

    Just to nitpick a bit, 10 K (as the article mentions) is really quite easy to achieve with off-the-shelf cryogenic equipment, and not the "near absolute zero" as the summary sort of suggests (I usually reserve this for 1 K, but maybe this is just me).

    1. Re:Absolute Zero by hamster_nz · · Score: 5, Funny

      Must be just you...

      * When I need a hat on it's cold

      * When my beer in the truck freezes overnight then it's really cold

      * When the diesel in my truck freezes overnight then it's really cold.

      * When my desktop maser works without any external cooling, then it's near absolute zero.

    2. Re:Absolute Zero by trout007 · · Score: 2

      When my Helium has a positive JT coefficient it's really cold.

      --
      I love Jesus, except for his foreign policy.
    3. Re:Absolute Zero by TubeSteak · · Score: 4, Interesting

      You know what's better than having to use off-the-shelf cryogenic equipment?
      Not having to use it.

      IMO, this is the real news:

      He came across a decade-old publication by Japanese researchers suggesting that when the electrons in pentacene are excited by a laser, they configure such that the molecule could work as a maser, possibly even at room temperature.

      I wonder how many other scientific breakthroughs are just sitting around waiting for anyone to conduct basic followup on a research paper.

      --
      [Fuck Beta]
      o0t!
    4. Re:Absolute Zero by Grog6 · · Score: 1

      It always struck me as strange how you can use liquid nitrogen to help recondense liquid helium; the little sterling engine makes the coolest noise...

      --
      Truth isn't Truth - Guliani
    5. Re:Absolute Zero by Arabian+Nights · · Score: 1

      To be fair, I don't think your arbitrary distinction is any better than theirs. It sound ridiculous, but in my work I consider anything warmer than 0.4 K "warm" because of how much technology and engineering you need to to best it (working on a dilution refrigerator). I'm sure there is someone working with nuclear demagnetization who balks at my standard, too.

      Accepting that, I think it's perfectly fine for the public to refer to 10 K as "nearly absolute 0" because on the typical public-used temperature scale (e.g., for weather), 10 K is unfathomable.

    6. Re:Absolute Zero by mdielmann · · Score: 2

      If only scientists were paid to review other scientists' work, replicate it, and maybe build upon it. But that doesn't get you grant money, usually. That's more often reserved for new work or application, it seems.

      --
      Sure I'm paranoid, but am I paranoid enough?
    7. Re:Absolute Zero by Anonymous Coward · · Score: 0

      Don't get me wrong, I think this is awesome! I work in a lab where we do often go to "near absolute zero" and would kill for the same phenomena to work at ~10K (it's easy!). As far as applications go, yes you don't want to use 50+ K worth of cryogenic equipment that requires constant maintenance and extremely inefficient operation. Physorg has more info on the cool applications: http://phys.org/news/2012-08-maser-power-cold-demo-solid-state.html .

    8. Re:Absolute Zero by CurryCamel · · Score: 1

      Well, this guy did it. And I bet he now has no problems getting more funding. That is point of reserving money for new work - you don't know what you might get, when building on other people's work you get the benefit of hindsight.

    9. Re:Absolute Zero by Anonymous Coward · · Score: 0

      You must be joking. The problem is generally believed to be the exact opposite. The publish or perish culture combined with a refusal to accept risk of failure has been bemoaned to result in most academic work being dedicated to the safe option of incremental progression on the work of others. This translates in to a depressingly slow rate of innovative and groundbreaking research.

    10. Re:Absolute Zero by Yvanhoe · · Score: 4, Informative

      Just to elaborate :

      - Liquid nitrogen boils at 77 K (â'196 ÂC; â'321 ÂF), it is very cheap and a hobbyist can get this easily.
      - Liquid helium boils at 3-4 K and is also produced industrially.
      If you have something that requires a low temperature but no lower than 77K, it is very easy : just dip it in liquid nitrogen.
      If you have something that requires 10K, it is "easy" also : put it into liquid helium.
      I think it is fair to say that "near absolute zero" is a sentence that supposes heavy cryogenic installations. 10 K is far easier than that.

      --
      The Wise adapts himself to the world. The Fool adapts the world to himself. Therefore, all progress depends on the Fool.
    11. Re:Absolute Zero by Yvanhoe · · Score: 4, Informative

      I wonder how many other scientific breakthroughs are just sitting behind paywalls waiting for anyone to conduct basic followup on a research paper.

      Here, fixed that for you. As a CS professional and biology hobbyist, I once decided to use my free time to get a specialization in gerontology genomics and to help open source projects in bioinformatics. I then discovered that 90% of the papers in the field are behind paywalls that even some universities can't access. I needed to read maybe 100-200 papers to have a good view of the field. At 25$ each, it made it expensive to volunteer freely for research projects...

      --
      The Wise adapts himself to the world. The Fool adapts the world to himself. Therefore, all progress depends on the Fool.
    12. Re:Absolute Zero by bill_mcgonigle · · Score: 1

      I wonder how many other scientific breakthroughs are just sitting around waiting for anyone to conduct basic followup on a research paper.

      And that in the subsequent decade the Japanese researchers didn't do what these guys did. Strange, they'd probably have a compelling business in operation by now.

      --
      My God, it's Full of Source!
      OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
  7. Re:Cold Fusion? by Anonymous Coward · · Score: 0

    "In the long term it could find a use in communications, but it first needs to be refined."

    Details, details ...

  8. Re:Cold Fusion? by geekoid · · Score: 3, Insightful

    Because you are a knee jerk moron who can't actual read the entire description, much less the article, before pounding your meat hooks into your key board in some vain attempt at a brow furrowing thought?

    --
    The Kruger Dunning explains most post on /. http://en.wikipedia.org/wiki/Dunning%E2%80%93Kruger_effect
  9. Powered by... by Anonymous Coward · · Score: 4, Funny

    "Using spare chemicals, a laser bought on eBay and angst from a late-night argument, physicists have got the world's first room-temperature microwave laser working."

    Getting this to work reliably is going to require a reliable source of angst. Any high school should do the trick.

    1. Re:Powered by... by rwven · · Score: 2

      The most annoying thing about this is that the dude had it built for three days and refused to turn it on out of fear of failure. Kudos for getting it done and a slap for being a wuss about it.

    2. Re:Powered by... by lister+king+of+smeg · · Score: 1

      So if it is powered off of angst does that mean we can power it off of twilight dvd's and books?

      --
      ---Saying gnome 3 is better than windows 8 not so much a compliment as it is damning with light praise.
    3. Re:Powered by... by Zan+Lynx · · Score: 1

      I'm like that whenever I buy a new computer part. Sometimes it sits in the box for weeks.

    4. Re:Powered by... by camperdave · · Score: 1

      When the difference between success and failure is the difference between microwaving the Jiffy-Pop while it is still in the cupboard, and the expression "Ow! My sperm!", I'd be hesitant as well.

      --
      When our name is on the back of your car, we're behind you all the way!
    5. Re:Powered by... by rwven · · Score: 1

      RTFA. He didn't turn it on because he was nervous it wouldn't work...

    6. Re:Powered by... by Anonymous Coward · · Score: 0

      Exactly! Wouldn't work... as in, instead of a nice coherent beam focussing on some popcorn, it sprays radiation all over the place, inflicting bodily harm to something that should never, ever be microwaved.

      One Whoosh for you.

    7. Re:Powered by... by c0lo · · Score: 1

      Getting this to work reliably is going to require a reliable source of angst. Any high school should do the trick.

      TFA:

      The final impetus came from an argument with his wife.

      Seems like the problem has been taken care.

      --
      Questions raise, answers kill. Raise questions to stay alive.
  10. Re:Cold Fusion? by chris+mazuc · · Score: 1

    no idea what the journals credibility is either.

    You've never heard of Nature?

    --
    E pluribus unum
  11. Super Wow by Anonymous Coward · · Score: 2, Interesting

    This is frikken huge news, if it pans out. I'm old enough to remember when news of the first MASERs came out. Before LASERs.
        Just the applications alone in Atomic Spectroscopy, ECR technology, high power communications- do you realize just how sloppy the frequency spread of Klystrons and similar devices are? Accelerator Technology, space charge cooling,... the implications for Fusion research...
        Super Wow.
        If it pans out.

    1. Re:Super Wow by m6tt · · Score: 1

      This could be great for p2p 802.11 links of some kind as well...I wonder if having the beam coherent would have any effect on things like rain and fog effects...

  12. Re:but can you mount it in sharks' heads? by Anonymous Coward · · Score: 0

    If they are kept at room temperature.

  13. Re:Cold Fusion? by Anonymous Coward · · Score: 0

    Because you didn't read the article?

  14. Neat, but..... by Anonymous Coward · · Score: 0

    Neat, but generating high power, coherent microwaves is pretty simple now, not so before III-V semiconductors. I have read about their usefulness for space power beaming.

  15. A microwave 100 million times more powerful? by Anonymous Coward · · Score: 1, Funny

    This is a thread I'll get my popcorn for.

    1. Re:A microwave 100 million times more powerful? by Anonymous Coward · · Score: 0

      You get the popcorn and sneak it into Hathaway's house. I'll get the target coordinates computed for trajectory adjustment.

  16. Re:Cold Fusion? by KaInDaWg · · Score: 0

    You Mad Bro?

  17. Re:Cold Fusion? by Anonymous Coward · · Score: 0

    Nature, is that the stuff outside my window?

  18. Re:Cold Fusion? by geekoid · · Score: 0

    I'll never feel better as long as lazy, ignorant opinionated fools keep spouting nonsense and not be called on it.
    so, no.

    --
    The Kruger Dunning explains most post on /. http://en.wikipedia.org/wiki/Dunning%E2%80%93Kruger_effect
  19. Re:Cold Fusion? by Anonymous Coward · · Score: 1

    Your mom's basement has a window?

  20. Conservation of angst by bigtrike · · Score: 1, Insightful

    This may drain all of the angst out of the entire school, altering youth forever.

  21. With a tracking magnetic mirror by Anonymous Coward · · Score: 1

    ... you could vaporize a man sized object from space...

    1. Re:With a tracking magnetic mirror by Anonymous Coward · · Score: 0

      Or write half your name on the moon before some freakazoid comes and stops you?

  22. I want diagrams, temperatures, power figures, etc. by Wierdy1024 · · Score: 0, Redundant

    Considering this is Nature, the lack of any numbers, or even a link to a paper are very disappointing. The writing style itself makes it sound like they've just turned lead into gold as well...

    I want diagrams, temperatures, power figures, etc. Not waffle. I expect better.

  23. Re:I want diagrams, temperatures, power figures, e by Anonymous Coward · · Score: 5, Informative

    Actually, the link to the proper paper is at the bottom in the references part, with a good description of results. Here is a direct link: http://www.nature.com/nature/journal/v488/n7411/pdf/nature11339.pdf

  24. Re:Powered by... Creme Brule?!? rtfa by j-stroy · · Score: 1

    Now this is my sort of science! I expect that this discovery has been made several times before with a predictable outcome; hence its "undiscovered" status.

  25. Re:Cold Fusion? by symbolset · · Score: 5, Funny

    You may be destined for a long unpleasant online experience.

    --
    Help stamp out iliturcy.
  26. Re:Cold Fusion? by prezkennedy.org · · Score: 1

    Reading sure is hard isn't it? Maybe you should head back on over to Digg... Oops...

    --
    It started back in Team Fortress Classic
  27. Like SimCity2000 by Anonymous Coward · · Score: 0, Insightful

    Here we unlock microwave power plants, next unlock is fusion so get excited!

    1. Re:Like SimCity2000 by Anonymous Coward · · Score: 0

      Man I so wish that is true. 2050 here we come.

    2. Re:Like SimCity2000 by mister_playboy · · Score: 1

      That game taught me to not live near such a power plant.

      You don't want to be near by when the satellite mis-aims it's beam...

      --
      Do what thou wilt shall be the whole of the Law ::: Love is the law, love under will
  28. Re:Cold Fusion? by Anonymous Coward · · Score: 0

    I didn't read the article and no idea what the journals credibility is either.

    You don't know what the credibility of Nature is? The door is that way, kid. Do let it hit you on the arse on your way out.

  29. Re:Cold Fusion? by Anonymous Coward · · Score: 0

    The Arsenic in DNA instead of Phosphorus was published in "Science", another widely respected journal.

  30. Re:Cold Fusion? by drkim · · Score: 4, Funny

    Your mom's basement has a window?

    Well, it's 'technically' a poster of two girls standing on the beach... not a real window.

  31. room temperature maser is not novel by Anonymous Coward · · Score: 0

    For an example, this group was creating room-temperature masers in the mid-90's: http://walsworth.physics.harvard.edu/research/pastprojects/atomicclock.html

    1. Re:room temperature maser is not novel by bmo · · Score: 4, Insightful

      But those aren't solid-state. This is.

      That's why it's a breakthrough. Solid state laser diodes got us optical media, fiber optics, 3d scanners, etc, because they're not fragile, big, and expensive like gas lasers. Gas masers are big, expensive, and fragile and need specialized technicians to keep running. Solid state masers you can take out in the field. You can put them in a hand-held device. Plus it's cheap. Really cheap. I just looked up the cost of p-Terphenyl and it's $165 for 100 grams of scintillation grade. That's a lot of crystal, and the dopant is $64 for 100mg. While that's a lot more expensive than platinum, it's a dopant - you only need a tiny amount in a crystal, on the order of .05%. 100mg of dopant can tint 200g of p-Terphenyl.

      Applications? It will revolutionize microwave comms and broadcast links. Microwave tower links are everywhere but the problem is there are so many and interference is a huge issue. A tower-to-tower maser link is not going to be as prone to spreading and causing interference and doesn't require the power of current microwave links. Broadcast and comms engineers are already salivating at the prospects. And that's just one application.

      --
      BMO

    2. Re:room temperature maser is not novel by Anonymous Coward · · Score: 0

      One assumes that if it is as powerful as they claim, and that it scales, you could reasonably use a high power solid state maser to transmit a sensible amount of power from a geostationary solar array? Sim City 2000 here we come!

    3. Re:room temperature maser is not novel by Anonymous Coward · · Score: 0

      You can put them in a hand-held device. Plus it's cheap.

      Applications?

      Medical Tricorder for all GPs! Stethoscopes go to history.

  32. Re:Cold Fusion? by interkin3tic · · Score: 1

    It's okay, we've all said stupid stuff online before and regretted it. I really wish slashdot had an option to moderate your own posts down to "-2: redacted".

    Or I wish I just stopped putting my foot in my mouth. That might be better.

  33. Re:I want diagrams, temperatures, power figures, e by tyrione · · Score: 2

    One demanding citations of work would expect to know to look in the citations section.

  34. microwaves radiation is still light by junglebeast · · Score: 1

    "most in the field gave up on masers and moved on to lasers, which use the same principles of physics, but work with optical light instead of microwaves."

    what the hell? microwaves are still EM radiation. EM radiation is light. thus a maser is just a regular laser in a different wavelength, no more different from a green laser vs a red laser....which are also just different wavelengths of light.

    1. Re:microwaves radiation is still light by Anonymous Coward · · Score: 0

      what the hell? microwaves are still EM radiation. EM radiation is light. thus a maser is just a regular laser in a different wavelength, no more different from a green laser vs a red laser....which are also just different wavelengths of light.

      Except that that wavelength is critical, the wavelength is very different to in optical light. That means you get very different effects which is why masers are so desirable, but it's also why until now they've been so hard to make.

      As an analogy green and red lasers are like green and red apples, while a maser's an orange. Ok they're all fruit, but the green/red apples are basically the same thing but the orange is something very different.

    2. Re:microwaves radiation is still light by Flipstylee · · Score: 1

      Mod parent up.

    3. Re:microwaves radiation is still light by lee1 · · Score: 2

      I only see the term "maser" in popular accounts of science. In my experience the people who work on them call them "lasers", "free-electron lasers" (FELs), "microwave lasers", etc. And microwave lasers have been commonplace for decades in the form of FELs. What's new here is the "solid state" part.

    4. Re:microwaves radiation is still light by danlip · · Score: 1

      The quote says "optical light", which means the range visible to humans. The quote also says "the same principles of physics", which could easily be interpreted to mean "still EM radiation". So there is nothing wrong with that quote.

    5. Re:microwaves radiation is still light by Amouth · · Score: 1

      actually.

      optical light is a form of EM radiation
      microwaves are form of EM radiation

      optical light is not any form of microwave
      microwaves are not any form of optical light

      optical light is a defined band in the possible EM radiation wavelengths and so is microwaves, but the two defined bands do not at all intersect

      --
      '...if only "Jumping to a Conclusion" was an event in the Olympics.'
    6. Re:microwaves radiation is still light by Anonymous Coward · · Score: 0

      I only see the term "maser" in popular accounts of science.

      There are 2000 references to masers in arXiv alone.

    7. Re:microwaves radiation is still light by sjames · · Score: 1

      You might notice given a cursory inspection that EM radiation at differing wavelengths can behave quite differently. So much so that the equipment really isn't interchangeable. That's why you don't see homebrew CT scans being done with overclocked keychain flashlights, for example. Likewise, you can't just crank the frequency knob on a ham transmitter and use it as an improvised security light.

  35. Sweet... by DaneM · · Score: 1

    The next step seems to be a portable power supply...

    = Maser Gun! Nice.

  36. Re:Cold Fusion? by Anonymous Coward · · Score: 0

    Is it really a poster of two girls, not women? I bet the lack of boobs tricked you into the faulty behaviour of wondering about nature. Ask your mom to exchange it so you can concentrate on the bare essentials.

  37. Re:Cold Fusion? by Soporific · · Score: 1

    It sure is, especially on your blog. I love it! Matt for President!!! Oops...

    Hah, that was funny wasn't it? If only I had your Maser like wit.

    ~S

  38. Re:Cold Fusion? by Soporific · · Score: 1

    You are ruining the credibility of the elderly there AC.

    ~S

  39. Re:Cold Fusion? by Anonymous Coward · · Score: 0

    Of course. True nerds don't like Windows. :-)

  40. Good start, but let's rein in the enthusiasm a bit by Muad'Dave · · Score: 2

    It may be 100 Million times as strong as its predecessor, but in absolute terms it required 1.5 KILOWATTS of input power to generate 100 MICROWATTS of output power. Not the most efficient thing in the world - that's an input:output power ratio of 15 million:1 (nearly 72 dB).

    --
    Tiller's Rule: Never use a word in written form that you've only heard and never read. You will end up looking foolish.
  41. Re:Good start, but let's rein in the enthusiasm a by Anonymous Coward · · Score: 0

    Yeah, but even if you had NO improvement and illuminated the crystal with a 30 dBm (1 watt) laser, let's see here. 30 dBm - 72 dB = -42 dBm. That's still a lot of power. Especially if you're beaming data in a narrow, coherent beam at something at 30 or 70 GHz.

    Don't try to scare people away by bringing up terms which you don't understand. A microwatt is a lot of power at these frequencies.

  42. Re:Good start, but let's rein in the enthusiasm a by necro81 · · Score: 2

    Perhaps, but when the incoming microwave signal is measured in nanowatts or picowatts, a gain of 100 million is pretty damned awesome. Bulk electrical power is easy to come by; a stronger incoming signal is very hard to come by. Depending on the application, who cares if the efficiency of the equipment is lousy.

    A better way to look at "efficiency" is to consider how much energy is required to transmit some unit of information across a certain distance. 1.5 kW electrical power is not actually all that much power for microwave transmission applications, especially if it means that the transmitter power can be turned down by, say, a factor of 10.

  43. Re:Good start, but let's rein in the enthusiasm a by Muad'Dave · · Score: 1

    I should have quoted this part of the article: "When configured as an oscillator, the solid-state maser’s measured output power of around 10 decibel milliwatts is approximately 100 million times greater than that of an atomic hydrogen maser, which oscillates at a similar frequency (about 1.42 gigahertz)." [emphasis mine].

    I was not referring to it's gain as an amplifier; rather it's rather meager output as a 1.42 GHz oscillator. For 1.5 kW in, I'd expect at least half that much power out to be considered useful at all (that's for a solid-state or tube oscillator).

    Here's a tunable VCO that uses 50mW to generate 2.5 mW from 1.277 to 1.691 GHz. That's 20:1.

    The only use this thing has as an oscillator over other means are possibly frequency stability and coherence, neither of which are major concerns with regard to microwave transmission applications.

    --
    Tiller's Rule: Never use a word in written form that you've only heard and never read. You will end up looking foolish.
  44. Re:Good start, but let's rein in the enthusiasm a by Anonymous Coward · · Score: 0

    The only use this thing has as an oscillator over other means are possibly frequency stability and coherence, neither of which are major concerns with regard to microwave transmission applications.

    The efficiency is crap; certainly this maser is not a transmitter, unfortunately. A hugely powerful pencil thin coherent microwave beam is pretty interesting to think about.

    Frequency stability is actually a major issue at higher microwave frequencies. Yes, a high quality crystal oscillator is pretty darn stable, but they are limited to fundamental resonances in low VHF; microwave frequencies require overtone oscillation or frequency multiplication, which both introduce noise and instability. This is obviously not a show stopper as we have been using microwave comms for half a century, but R&D is still ongoing.

    A maser, on the other hand, can be used to build an atomic clock; it's stability at high frequencies really kicks the snot out of any XO. Even if it doesn't find common applications in the field, it will almost certain find applications in lab frequency references, GPS systems, satellites, etc.

    Weak signal reception sounds like a huge potential application. This may obsolete the GaAsFET for weak signal amplification. Although being at room temperature, I doubt it could reach a 17k noise floor.

  45. Re:Good start, but let's rein in the enthusiasm a by sjames · · Score: 1

    Considering that he got that first try with a far from perfect crystal he cooked up in a hurry, it's reasonable to expect some rapid improvements now that we know it''s not a complete waste of time.

  46. Liquid N2 vs. H2 vs. He vs. 10K by billstewart · · Score: 1

    Yes, you can use liquid helium to cool it, and it's probably easier than running your own cryogenic cooling pumps. But unfortunately it's not cheap - it's about $10/liter, vs. less than $1/liter for liquid hydrogen or $0.10 for liquid nitrogen. And there's a limited supply of helium in the world, so it's likely to be getting more expensives. (Liquid H2 temperature is about 20K, so it's not quite enough for a maser that needs to be 10K.)

    Room-temperature masers are much more practical. And they're a lot easier to attach to sharks.

    --

    Bill Stewart
    New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
    1. Re:Liquid N2 vs. H2 vs. He vs. 10K by Yvanhoe · · Score: 1

      You have to admit that having to attach a cryogenic system on the shark also has a touch to it, too...

      --
      The Wise adapts himself to the world. The Fool adapts the world to himself. Therefore, all progress depends on the Fool.
  47. Re:Room-Temperature Masers by Anonymous Coward · · Score: 0

    More like Turtles with frikkin' Masers.
    [S->T; L->M]

  48. Re:Good start, but let's rein in the enthusiasm a by Muad'Dave · · Score: 1

    I agree completely (that's why I said "Good start"), but the wild, rabid enthusiasm of other commenters need to take that into account. They obviously didn't RFTA, so they hear 'maser' and thought it meant 'death ray'.

    PS - I think you may have made it onto the DEA's watch list with your phrase "crystal he cooked up in a hurry". :-)

    --
    Tiller's Rule: Never use a word in written form that you've only heard and never read. You will end up looking foolish.
  49. Re:Good start, but let's rein in the enthusiasm a by Muad'Dave · · Score: 1

    Don't try to scare people away by bringing up terms which you don't understand. A microwatt is a lot of power at these frequencies.

    I definitely understand the terms and agree that -42dBm is a useful amount of power at 60GHz. Thanks for the ad hominem.

    My point is that if you've got all that power and all that real estate to run such a large and terribly inefficient signal source, what does using it actually give you?

    In any real-world comms application I can think of (outside the laboratory), spatial and temporal coherence are not needed and introduce more problems that they solve. The beamwidth is narrow but is still diffraction-limited; the same limit can easily be achieved with normal high gain antennas (at 30-70GHz, high gain antennas are tiny).

    If for some reason you need temporal coherence, your only choices of modulation are by direct modulation of the pump laser; that is, mixing (heterodyning) the output of the maser with a modulating signal by conventional means (semiconductor mixer, for instance) would destroy the coherence. I suppose you could do the mixing in a non-linear waveguide setup, but that would be a lot of microwave plumbing. Similar results can be achieved using regular old polarized antennas without limiting your modulation choices.

    In other words, using a maser for comms is a solution looking for a problem.

    In your example, a 1 watt optical laser would be at best 45% efficient. So you're looking at about 2.2 Watts input for 63 uW out. A 20 GHz DRO followed by a doubler or tripler would give you significantly more output power per unit of input power, as well as be tunable and tiny. The DRO in the link consumes a maximum of 31.7 dBm of power and emits 13 dBm of RF. an IMPATT diode would be another good choice.

    --
    Tiller's Rule: Never use a word in written form that you've only heard and never read. You will end up looking foolish.
  50. Re:Cold Fusion? by Anonymous Coward · · Score: 0

    You forgot your own ~Snarky tag. ;-P

  51. Re:Cold Fusion? by AK+Marc · · Score: 1

    What, so you are looking for someone to call you on it?