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Room Temperature Semiconductor of T-Rays

Posted by CmdrTaco on from the but-what-does-it-mean-man dept.

Fallen Andy noted a Physorg story that says "Engineers and applied physicists from Harvard University have demonstrated the first room-temperature electrically-pumped semiconductor source of coherent Terahertz (THz) radiation, also known as T-rays. The breakthrough in laser technology, based upon commercially available nanotechnology, has the potential to become a standard Terahertz source to support applications ranging from security screening to chemical sensing." "What did you do at the office today, honey?" "Oh, I just demonstrated the first room-temperature electrically-pumped semiconductor source of coherent Terahertz radiation. How was your day, dear?"

110 comments

  1. But wait! by Malevolyn · · Score: 2, Funny

    What about the powerful z-ray?

    --
    Your ad here.
    1. Re:But wait! by peragrin · · Score: 1

      I would be more worried about the t-rays mutating into the t-virus.

      I do have my shotgun, and hand to hand weapons ready though. I figure i can pick up a couple of assault rifles from fallen police officers.

      --
      i thought once I was found, but it was only a dream.
    2. Re:But wait! by Yvan256 · · Score: 1

      What about the infanto ray?

    3. Re:But wait! by Anonymous Coward · · Score: 0

      What about the powerful z-ray? is two better than x...
    4. Re:But wait! by mrmeval · · Score: 2, Funny

      Most departments only allow semi-auto rifles except for the el1te units. Besides you have to aim for the head and full-auto is to keep their heads down and stop massed attacks.

      Zombies don't duck.

      http://zombiehunters.org/

      --
      I'd go on a Vegan diet but the delivery time from Vega is too long. --brownkitty
  2. Sharks? by adpsimpson · · Score: 4, Funny

    Does it come with a shark-head mount?

    The summary leaves me unsure.

    --
    Is crushing a suspect's child's testicles illegal?
    John Yoo: "No, [if] the President thinks he needs to do that."
    1. Re:Sharks? by somersault · · Score: 1

      I have received a message from the T-Rays, they say "We ain't gettin on no shark, sucka!"

      --
      which is totally what she said
    2. Re:Sharks? by xpuppykickerx · · Score: 1

      And does Frau Farbissina have to signal the firing of said laser?

    3. Re:Sharks? by famebait · · Score: 1

      Sharks are for lasers. T-rays, as everyone knows, are carried by platypi.

      --
      sudo ergo sum
  3. Coherent by alexj33 · · Score: 0

    I for one welcome our coherent radiating overlords.

  4. What can T-Rays do? by Anonymous Coward · · Score: 0

    What do we know about the properties of T-Rays?

    1. Re:What can T-Rays do? by JustOK · · Score: 5, Funny

      Very strong,dangerous and powerful, but with teeny-tiny arms

      --
      rewriting history since 2109
    2. Re:What can T-Rays do? by brunokummel · · Score: 1

      aaah let me see.. Just Wiki it ??

      --
      What is best in life? To crush your enemies, to see them driven before you and to hear the lamentations of their women.
    3. Re:What can T-Rays do? by mckinnsb · · Score: 5, Informative

      From reading the article, my layman's-"I'm no physicist"'s take on T-Rays:

      1) They can penetrate through clothing/plastic/flesh, and most of the materials mentioned seem to be organic in nature. This gives them "X-ray"-like properties.
      2) They were able to make T-Rays before in laboratories, but now they can make them more cheaply, with less power, in human-friendly settings.
      3) T-Rays give off less radiation than X-rays, due to the much larger wavelength.

      Quick Conclusion: We now have the potential to create an X-ray like device that could be deployed in airports and other travel hubs that could be used to monitor the public without harming the public through this observation. More benignly, they could also be used in hospitals for "persistent monitoring" of patients with tumors or internal bleeding, because they seem to have lower power requirements and risks of side-effects.

    4. Re:What can T-Rays do? by Yvan256 · · Score: 1

      Also, don't let Newman anywhere near a computer.

    5. Re:What can T-Rays do? by kestasjk · · Score: 4, Informative

      In fact the spectrum from microwaves to visible light is on the scale of THz, though specifically they refer to the portion between microwave and infra-red. They're really nothing like X-rays which are way over on the other side of visible light.

      So on the one hand you have visible light and infra-red which ca\n't go through anything, on the other side you have microwaves which can go a short way through a soup or frozen chicken, and in the middle you have "T-rays" which can go through clothing but not weaponry and body parts.

      Not sure exactly why IR and microwaves have been so easy to generate while "T-rays" are so difficult, and I wish they'd come up with a better name than "T-ray" because technically visible light and infra-red are THz too.

      --
      // MD_Update(&m,buf,j);
    6. Re:What can T-Rays do? by Anonymous Coward · · Score: 0

      Right, because Wikipedia should be the #1 resource for all information, it being totally reliable.

    7. Re:What can T-Rays do? by Kingrames · · Score: 3, Funny

      And the real kicker is that One T-Ray can beat the crap out of three velocirays in any standard unit of fight.

      --
      If you can read this, I forgot to post anonymously.
    8. Re:What can T-Rays do? by Gilmoure · · Score: 2, Funny

      Can they be mounted on a set of dark rimmed glasses? Do they work at the beach?

      --
      I drank what? -- Socrates
    9. Re:What can T-Rays do? by kabocox · · Score: 1

      Quick Conclusion: We now have the potential to create an X-ray like device that could be deployed in airports and other travel hubs that could be used to monitor the public without harming the public through this observation. More benignly, they could also be used in hospitals for "persistent monitoring" of patients with tumors or internal bleeding, because they seem to have lower power requirements and risks of side-effects.

      Just wait for the tech to drop to $50-500 and some one to figure out how to hook it up to your next PS or Xbox for both daily med scans and home security.

    10. Re:What can T-Rays do? by Anonymous Coward · · Score: 0

      From what I've read, the see-thru-chicks-clothes THz airport scanner is passive - receive only, which seems to imply that THz radiation is maybe also present in visible light sources (or maybe we generate it?). Or maybe they are lying and while the receiver is passive, there is also a seperate THz illumination device required? Does anyone know what the truth is?

      Presumaby THz illumination (not necessarily lasers) would certainly enhance THz imaging just as appropriate (visible, infra-red) lighting enhances any type of photography.

    11. Re:What can T-Rays do? by soibudca · · Score: 1

      An even more intriguing consequence stems from the fact that this is a _coherent_ light source. This means all the advantages of coherent light may be brought to bear on diagonostic / characterization problems. For example a holographic image of a patient could be constructed with a single exposure (without the requirements costs and limitations of something like a tomographic reconstruction obtained from a CT scan).

    12. Re:What can T-Rays do? by dlenmn · · Score: 3, Informative

      3) T-Rays give off less radiation than X-rays, due to the much larger wavelength. It's not that they give of less radiation, it's that the radiation is non-ionizing (meaning that no photon has enough power to knock a electron free from its atoms -- that's what allows x-rays and UV to do damage). Because of how quantum mechanics works, you can blast away with as many of these photons as you like (aka, as much radiation and power as you want) and it will still be non-ionizing. It's cool stuff.
    13. Re:What can T-Rays do? by Anonymous Coward · · Score: 0

      Yeah, that's exactly what he said! Way to powerfully refute his lame argument!

    14. Re:What can T-Rays do? by rcw-work · · Score: 1

      From what I've read, the see-thru-chicks-clothes THz airport scanner is passive - receive only, which seems to imply that THz radiation is maybe also present in visible light sources (or maybe we generate it?).

      We do generate it. Everything does, through black body radiation. According to Wien's displacement law, the peak frequency for something at 300 Kelvin is about 30 THz.

      For many imaging applications, though, it's more useful to "light up" something and see the reflection. Kinda like using a camera flash.

    15. Re:What can T-Rays do? by njh · · Score: 0

      Room temperature blackbodies emit plenty of THz radiation. The peak at 293K is 30THz and a surface at 293K emits 400W or so of radiation per m^2.

    16. Re:What can T-Rays do? by Anonymous Coward · · Score: 0

      That, plus I believe I read that t-rays would be good for high-speed wireless data transfer, and it would be easy to shield a room. This would allow wireless data transfer inside almost any room, without risk of someone outside the room being able to listen in.

    17. Re:What can T-Rays do? by Anonymous Coward · · Score: 0

      Except in the near field, where the wave properties of photons dominate and you can make the electric field arbitrarily strong. Thus I can light up fluorescent tubes with a 27MHz walkie-talkie, provided it has fresh batteries and it is in 4W transmit mode.

    18. Re:What can T-Rays do? by dietlein · · Score: 1

      1) They can penetrate through clothing/plastic/flesh, and most of the materials mentioned seem to be organic in nature. This gives them "X-ray"-like properties.
      Sorry, terahertz radiation cannot penetrate through flesh, in any manner comparable to X-ray radiation. We (our bodies) are pretty much water, when it comes down to it, and above 100 GHz, even 1 cm of water will attenuate a signal by several hundred dB. Refer to Kindt & Schmuttenmaer (1996) for the double-Debye model fit parameters.

      The images you probably have in mind are from reflectance-based measurements, rather than transmittance. They appear similar to X-ray images, but have very little in common.

      Clothing, common building materials, etc., are all fairly translucent to terahertz radiation.

      2) They were able to make T-Rays before in laboratories, but now they can make them more cheaply, with less power, in human-friendly settings.
      Basically.

      3) T-Rays give off less radiation than X-rays, due to the much larger wavelength.
      I think you meant to say that terahertz radiation has lower photon energy than X-ray radiation. That is true.
    19. Re:What can T-Rays do? by anmida · · Score: 1

      Nothing that we've had to work with so far emits coherent and narrow-band T-rays. These wavelengths lie between those that can be understood by quantum mechanics, and those of classical physics.

    20. Re:What can T-Rays do? by mckinnsb · · Score: 1

      1) No, it can't, but it can penetrate through a small portion of flesh, and is useful in determining fatty/non fatty tissue. "X-ray like" was not meant to be scientific in any way. :)
      2) Yep.
      3) I did, thanks. Again, I was speaking more in the vernacular. Never got a Physics degree.

    21. Re:What can T-Rays do? by Eskarel · · Score: 1
      Wikipedia is a perfectly reliable source of information for anything which isn't remotely controversial and which is relatively technical(so that the experts use computers a lot).

      No one is going to bribe Jimmy to change the entry on T-rays, and you're not going to find some fringe group gaming the system either(at least as far AFAIK), so it's probably pretty reliable.

      Wikipedia has its uses, it's just pretty useless for anything where there's any sort of argument or vested interest.

    22. Re:What can T-Rays do? by Andor666 · · Score: 1

      Have in mind that IR and UV can go through some milimeters of flesh. You can take IR photos, even with a point and shoot digital camera, and see veins i.e. on your arms. Also you can shoot UV, and see defects on your skin, or old hematomas. IR and UV are also used in art, for seeying through old layers of paint, and knowing how paintings where a lot of years ago, or how where painted, or maybe, if there is any different sketch under the painting...

    23. Re:What can T-Rays do? by Bloodoflethe · · Score: 1

      Except for the random person who inserts references to hot dogs and the like in scientific pages.

      --
      "Little is much when little you need."
    24. Re:What can T-Rays do? by Anonymous Coward · · Score: 0

      Not sure exactly why IR and microwaves have been so easy to generate while "T-rays" are so difficult,

      Microwaves are in the gigahertz range, so they can be generated with conventional circuitry. T-rays cannot, the frequency is too high.

      IR and visible radiation can be generated by heating things up until they glow (for IR the glow is not visible), or by using "electron band gaps" as in LEDs and lasers. But room temperature is already warm enough to create lots of ambient IR radiation which overwhelms the lower-energy T-rays. I think "band gaps" are useless for T-rays for essentially the same reason.

  5. Commercially available nanotechnology by reallyjoel · · Score: 1

    Where can I buy me one of those?

  6. conversation by pablomme · · Score: 1

    - What did you do at the office today honey?
    - Oh, I just demonstrated the first room-temperature electrically-pumped semiconductor source of coherent Terahertz radiation. - What?
    - Put goggles on, pressed button, computer said "pretty coherent!", had lunch.
    - Oh.. I thought you had to be clever to be a physicist..
    - Nah, monkeys do this all the time.
    --
    The state you are in while your HEAD is detached... - wait, what?
    1. Re:conversation by Goffee71 · · Score: 4, Funny

      First - don't call us monkeys!

      Second - Dang, humans have penetrated the underground ape-lab and found our laser test rig for the grand deconfibrulatex that will return us to mastery of this planet.

      KILL THEM ALL!

      --
      If he's the Walrus then can I be a penguin please?
    2. Re:conversation by ttapper04 · · Score: 1

      "...the goggles, they do nothing!"

      Obligatory

    3. Re:conversation by neomunk · · Score: 1

      You laugh, but I've been praying for a scientist coup for a long time now. The 'normies' have enacted masochistic policies for too long now as the brilliant people have sat by, apparently not paying any attention to the results, and enabled them every step of the way.

      I say the next time scientists with the Good Equipment build the next paradigm changing weapon, keep it for yourselves and demand sanity in policy. That or just threaten to strike, taking the equipment home with you (a tall order, I know) so that your passion for discovery can still be satiated.

      Sorry about that, just had to plant a little dissent amongst those that have the ability to do something. :-D

  7. Oblig... by nih · · Score: 2, Funny

    Please refrain from looking at laser with remaining eye

    --
    I'm a rabbit startled by the headlights of life :(
  8. Re:But wait! Forget Z-Rays by Culture20 · · Score: 1
    From Ultima VII:

    MEMPTO RAYS: A QUALITATIVE STUDY
    IN METAPARAPHILOSOPHICAL RADIATION
    by Mempto

    Despite Felcrodan's theory of 0335, there are, indeed, rays of energy that constantly bombard Britannia. In fact, these very same rays permeate of all the known space between Britannia and the stars. Recent experiments have proven my theory that these rays, known hereafter as "Mempto Rays", are lethal to all non-living matter. In fact, Mempto rays have demonstrated their ability numerous times, once killing an entire boulder in a matter of a few hours. It is my recommendation...
  9. Article unit goof? by Wilson_6500 · · Score: 5, Insightful

    I was trying to decide if we should facetiously call this device a "taser" or "maser" when I realized that the article appears to give two different wavelength ranges for the device. The image caption seems to state that a 5-Thz wave corresponds to a 50 micrometer wavelength, whereas the article itself indicates that these lasers operate in the 3-30 nanometer wavelength range. Methinks someone used the angstrom symbol incorrectly, since 50 um * 5 Thz is about equal to the speed of light.

    So, with that aside, we still have to decide if this thing is a maser or a taser!

    1. Re:Article unit goof? by apodyopsis · · Score: 2, Funny

      Arg, I cannot help it....

      ...a phaser?

      for the geek factor alone, I'll gladly suffer the +5 redundant rightfully coming my way.

    2. Re:Article unit goof? by Yvan256 · · Score: 3, Funny

      I am stunned by your reply.

    3. Re:Article unit goof? by brunokummel · · Score: 1

      Well ... Taser is already taken...=P

      --
      What is best in life? To crush your enemies, to see them driven before you and to hear the lamentations of their women.
    4. Re:Article unit goof? by mckorr · · Score: 1

      Maser and Taser are already taken. One by microwave lasers (lasers with light in the microwave bands), the other by the Texas police. They're a bit taze happy here in Texas :)

    5. Re:Article unit goof? by Anonymous Coward · · Score: 0

      The term maser already has meaning in this context

    6. Re:Article unit goof? by apodyopsis · · Score: 1

      hehehe. I cannot help it again...

      the t-ray phaser that renders all your opponent's clothes see through! (I am visualising one fucked up trek episode there and then, "why yes captain, let me demonstrate the effect of the new weaponry on Uhuru"..

      golly, I could of done with one of those at the nightclub last week...

    7. Re:Article unit goof? by Anonymous Coward · · Score: 0

      I was trying to decide if we should facetiously call this device a "taser" or "maser" when I realized that the article appears to give two different wavelength ranges for the device. The image caption seems to state that a 5-Thz wave corresponds to a 50 micrometer wavelength, whereas the article itself indicates that these lasers operate in the 3-30 nanometer wavelength range. Methinks someone used the angstrom symbol incorrectly, since 50 um * 5 Thz is about equal to the speed of light.

      So, with that aside, we still have to decide if this thing is a maser or a taser! Its THaser baby thaser.
    8. Re:Article unit goof? by grrrl · · Score: 1

      Yep you're correct, especially since their angstrom has a lowercase a!

      In fact the summary is rather fluffy, I'll wait to read the APL :)

    9. Re:Article unit goof? by grrrl · · Score: 1

      Oh, the APL is out already - and yes the first line reads "The terahertz THz spectral range = 30 - 300 um has long been devoid of electrically pumped room temperature RT semiconductor source." (another great example of APL editing - should read devoid of _a_ source, or devoid of sources).

    10. Re:Article unit goof? by AdamHaun · · Score: 1

      How about a teaser (T-ser)?

      --
      Visit the
  10. Room Temperature Conductor of T-Rex by Ferzerp · · Score: 4, Funny

    That is what I read the title as. I had a weird symphony pictured in my head.

    1. Re:Room Temperature Conductor of T-Rex by JustOK · · Score: 1

      T-Rex had to conduct. Its arms are too short to play anything.

      --
      rewriting history since 2109
  11. X-Ray glasses by TropicalCoder · · Score: 1

    Next they will be selling X-Ray glasses made with this to kids with ads in comic books...

    1. Re:X-Ray glasses by Culture20 · · Score: 1

      Next they will be selling X-Ray glasses made with this to kids with ads in comic books... You haven't read a comic book recently; they're all used car classifieds and personal ads.
  12. zzzz by apodyopsis · · Score: 1

    Well I attempted to RTFA but it was waaay over my head.

    So I'll summerize some simple questions and hope there are some kindly physicists who can answer...

    1. will this help me see through girls clothing? (vaporising them and providing a 1ns window of "no clothing" does not count)

    2. does this provide any new interesting military technology with "cool!" factor?

    3. can T-rays diagnose all illnesses and promote world peace?

    4. is this anything like those airport sensors? is the world going to become crowded with sweaty palmed "security" people who are obsessed with looking through people's clothing?

    5. is hiring the security man of the future going to be like electing a president? (ie. anybody who wants the job should not have it)

    Answers on a postcard, much obliged.

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

      Answers on a postcard, much obliged. How about wikipedia instead.

      This really is a very important advance. It's sad that 99% of the comment here are jokes.
    2. Re:zzzz by SatanicPuppy · · Score: 1

      1. Yes, also their skin.
      2. T Rays are low energy, so not much profit in trying to kill someone with them. A nice rock would work better.
      3. Yes and no. They're better than X-rays for some diagnostics, but, as always, more knowledge = less peace.
      4. Yes. Except they don't see through clothes (those already exist) they look through clothes and skin. They also are more effective at spotting explosives, etc, due to peculiarities in their composition.
      5. This has always been the case.

      --
      ad logicam Claiming a proposition is false because it was presented as the conclusion of a fallacious argument.
    3. Re:zzzz by Gilmoure · · Score: 1

      Check out the subcutaneous fat on that babe! Hubba-hubba!

      --
      I drank what? -- Socrates
    4. Re:zzzz by Walt+Dismal · · Score: 1

      I agree, and I pity the fool who makes jokes about T-ray technology. Oh wait. You didn't say "Mr. T" ray technology. Ooops.

    5. Re:zzzz by neomunk · · Score: 1

      More like "OMG, those are REAL?!? Wow."

    6. Re:zzzz by dietlein · · Score: 2, Informative

      1. Yes, also their skin.
      No, not their skin. Kindt & Schmuttenmaer (1996). 1 cm of water attenuates frequencies above 100 GHz by several hundred dB.

      3. Yes and no. They're better than X-rays for some diagnostics, but, as always, more knowledge = less peace.
      X-rays and terahertz radiation are not really competitors in the medical field, due to the fact that terahertz radiation is attenuated greatly by water, and we're mostly water. You can detect some skin conditions with it, but only those in the first 1-3 mm of tissue. These are also visible to the naked eye, typically.

      Now, you can look through bandages to see if a wound is healed, yes. That could be useful, but we also like changing bandages too, so it's debatable.
    7. Re:zzzz by kesuki · · Score: 1

      i recall something about the airport usage of t-rays (and yes some airports use t-ray scanners to look for weapons, they don't scan everyone though, because the equipment was ver expensive until this new innovation.)

      I recall that the designers of 't-ray' devices had to patch their devices to 'blur' private regions, because people were getting upset that you 'could see too much detail' with the first t-ray scanners...

      making t-ray scanners 'cheaper' to build and operate will increase their use in airport security, but again, it can't see into body cavities for weapons... and there are certain kinds of plastic weapons (iirc) that don't show up in a t-ray scan, but almost all explosives and anything made of metal shows.

      --
      https://www.gnu.org/philosophy/free-sw.html
  13. Room tempurature?!?!! by martinQblank · · Score: 2, Funny

    Shouldn't they be focusing on ocean temperature?

    1. Re:Room tempurature?!?!! by StonedYoda47 · · Score: 1

      I hope this gets modded up. This provided a nice chuckle to my day.

  14. What we REALLY need by hyades1 · · Score: 2, Insightful

    I know there are lots more applications for this, but what the health care system could really use right now is cheaper imaging technology. I'd love to see a similar breakthrough that reduced the cost of an MRI machine to about five grand.

    --
    I've calculated my velocity with such exquisite precision that I have no idea where I am.
    1. Re:What we REALLY need by jd · · Score: 3, Informative

      With the evolution of very low power, high resolution MRI systems, that's entirely possible. Highly sensitive sensors are generally cheaper than 2.5T (and would be a LOT cheaper than 9.2T) magnets and accompanying shielding. On the other hand, any new field is going to take time to move from early uses to mainstream, and getting sensors to the limits of existing MRI technology is going to take a whole lot longer. (It's one thing to demonstrate basic imaging - which is quite good enough for many purposes. It's quite another to get to the point of imaging down to the level of individual neurons. I'm guessing the 12T magnets used in animal experiments provide far more detail yet.)

      --
      It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
    2. Re:What we REALLY need by TubeSteak · · Score: 0

      I know there are lots more applications for this, but what the health care system could really use right now is cheaper imaging technology. I'd love to see a similar breakthrough that reduced the cost of an MRI machine to about five grand. The only problem is, the cheaper the imaging, the more often it will be used.

      And the more often it is used, the more completely benign stuff you'll find.
      That means more follow ups, biopsies, consultations with experts, etc.
      And all that has a very real possibility of raising the costs of health care.

      So when you calculate the benefits, you have to calculate the cost of all the useless testing will happen and subtract that out.
      --
      [Fuck Beta]
      o0t!
    3. Re:What we REALLY need by drinkypoo · · Score: 1

      So when you calculate the benefits, you have to calculate the cost of all the useless testing will happen and subtract that out.

      What does it cost to move to a country with nationalized medicine, anyway?

      --
      "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
    4. Re:What we REALLY need by bitrex · · Score: 1

      I think it's unlikely that the price of scans will come down anytime soon, given that for many hospitals MRIs are a major cash cow. A modern scanner costs the hospital around $4 million, plus around a million a year for related salaries and maintenance. If they're doing an average of 15 scans per day (any major hospital with a scanner hits that number easily) and billing insurers an average of $2000 per scan (which from my experience is on the low end, my last MRI cost my insurance company $2900), they're pulling in near $11 million a year in gross profit. Plus the fact that the initial cost of the scanner is amortized over several years.

    5. Re:What we REALLY need by hyades1 · · Score: 1

      The last estimates I saw that made a serious attempt to do an apples-to-apples comparison indicated that the Canadian system delivers roughly twice the health care dollars to the sharp end (doctors, nurses, equipment and supplies, etc.) as the American model.

      That doesn't tell the whole story by any means, but it seems to indicate that the insurance companies which infest the American system are feeding very, very well.

      I don't know what the "start up" cost or "changeover" cost might be. Canada made the move so many years ago that I'm not sure any actions taken then would be relevant today.

      --
      I've calculated my velocity with such exquisite precision that I have no idea where I am.
    6. Re:What we REALLY need by WhoBeDaPlaya · · Score: 1

      It's not just the amount of field, it's the precision as well. One of the reasons why MRI is so clunky is that you have the main coil and then shim, tesseral, etc. coils to help "fine tune" the fields. Not to mention that the patients load the coils as well.

  15. T-rays for security, medicine by Speare · · Score: 3, Informative

    The blurb has a lot of jargon but no reference as to what uses T-rays are likely to be put. T-rays applications They're likely to help with certain cancer scans within the body, but these are also the basis for new "scan 'em naked at fifty paces" airport security cameras. I'm not sure I'm too excited about advancement in this technology just at the moment. Yeah, yeah, scanners don't scan people, overzealous control-freak post-democratic regimes scan people. But you get my drift.

    --
    [ .sig file not found ]
    1. Re:T-rays for security, medicine by xpuppykickerx · · Score: 1

      Health Care, Smealth Care! We need to learn how to focus these beams into 50 shot clips for WWII pistols that are modified into DL-44 blaster pistol.

    2. Re:T-rays for security, medicine by JustinOpinion · · Score: 2, Interesting

      In addition to the applications you mentioned (medicine and security), a more mundane application is in manufacturing and quality control. For instance, with these scanners you can automate the quality and consistency checks on many manufactured goods, including foods. For instance, the scans could visualize the internal dispersion of nuts in a candy bar, or the consistency of bread. It could also be very useful for detecting anomalous matter in food (e.g. pick out metal or a band-aid that accidentally found its way into the food), or detecting insects and larvae inside fruits and vegetables.

      The scans are totally benign and non-ionizing, so there's no health risks associated with scanning food.

    3. Re:T-rays for security, medicine by SatanicPuppy · · Score: 1

      T-Rays are better for this than the current "scan 'em naked" scanners, because they can be tuned to look for only weapons/bombs/whatever.

      From WP: Terahertz radiation can penetrate fabrics and plastics, so it can be used in surveillance, such as security screening, to uncover concealed weapons on a person, remotely. This is of particular interest because many materials of interest, such as plastic explosives, have unique spectral "fingerprints" in the terahertz range. This offers the possibility to combine spectral identification with imaging. Passive detection of Terahertz signatures avoid the bodily privacy concerns of other detection by being targeted to a very specific range of materials and objects.

      --
      ad logicam Claiming a proposition is false because it was presented as the conclusion of a fallacious argument.
    4. Re:T-rays for security, medicine by znerk · · Score: 1

      ooh... can we use it to check scratch-off lottery tickets prior to purchase?

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      This work is licensed under a Creative Commons Attribution 3.0 Unported License.
  16. Very nice. Here's the real source by Animats · · Score: 5, Informative

    First, here's the real paper. Actually, this is the previous paper, where they got operation at 177K, but not quite room temperature. (Don't link to Physorg; they just collect press releases, add ads, and delete the citations.)

    Terahertz waves are interesting. At one time, that was an inaccessible portion of the spectrum, above radio but below infrared. Now it's understood that it's a region in which both RF and optical techniques can work. At that frequency, propagation is line of sight, although diffuse systems, as with diffuse IR, are possible. Applications are still a ways off, but there's probably something useful to do with this stuff.

    Incidentally, "radio", by international agreement, ends at 3THz. Beyond that, it's "light" for regulatory purposes. In the US, FCC regulations (for RF) end at 3THz, and DHS regulations (as for lasers) begin.

  17. Room Temperature Semiconductor *Source* of T-Rays by Anonymous Coward · · Score: 0

    The T-ray source is made of semiconductor materials. It does not "semiconduct" T-Rays, whatever that would mean.

  18. T-rays have imaging and security applications by Reality+Master+201 · · Score: 2, Informative

    T-ray imaging systems are what are being proposed to scan people in airports and other secure places; you can get images under a person's clothing, so you can actually see what they might have concealed.

    Check out the wikipedia page: http://en.wikipedia.org/wiki/Terahertz_radiation

    1. Re:T-rays have imaging and security applications by jeffmeden · · Score: 2, Interesting

      So riddle me this: Why are Terahertz waves limited to "between 300 gigahertz (3x1011 Hz) and 3 terahertz (3x1012 Hz)" according to the article? Wouldn't it make sense for the scale to start somewhere around 1 THz and run to about 999 THz, where it would then run into Petahertz? Just curious, TIA!

    2. Re:T-rays have imaging and security applications by Reality+Master+201 · · Score: 2, Funny

      You and your silly insistence on consistent meanings for SI prefixes.

    3. Re:T-rays have imaging and security applications by Der+PC · · Score: 1

      So, basically it's your standard peeping tom camera ?

      Now I can't wait until all those T-ray porn sites start appearing :P

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  19. MST3K Ref by ewhac · · Score: 1

    Oh, I just demonstrated the first room-temperature electrically-pumped semiconductor source of coherent Terahertz radiation. How was your day dear?

    "Well, I isolated a nucleotide today..."

    Schwab

    --
    Editor, A1-AAA AmeriCaptions
    1. Re:MST3K Ref by Anonymous Coward · · Score: 0

      I also found the OP's concluding comment to be silly, as any of a number of researchers and inventors routinely preside over "firsts" in their job and THz generation needn't be singled out as some sort of generations-long Holy Grail quest that's now finally been realized to the rejoicing of all of Mankind. Innovation is part of the job description in all academic and industrial research labs.

    2. Re:MST3K Ref by TheSync · · Score: 1

      Oh yeah, I replicated thousands of strands of DNA today, just in the tip of my little finger!

  20. What's cooking? by flahwho · · Score: 0

    ...What did you do at the office today honey?
    Well, Here let me show you. Stand right right on this red X...

  21. No unit goof by supergumby · · Score: 4, Informative

    The units and quantities used in the article are correct. Two lasers, with wavelength in the range of 3 to 30 nanometers, shine into a magic box. Out of the magic box comes light with a wavelength which is the difference of the two input lasers. The magic box is a material with a nonlinear response to electromagnetic waves, such as gallium arsenide.

    1. Re:No unit goof by JustOK · · Score: 1

      All the more reason for space exploration. I've heard you can get arsenide from Uranus.

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      rewriting history since 2109
    2. Re:No unit goof by vsny · · Score: 2, Informative

      The units are *not* correct. The article is referring to THz wavelenghts in general (30-300um's) not the "two lasers". 3-30nm would be X-rays and GaAs is not creating X-rays. In fact there is not two lasers at all, that is not how a QCL works. The blurb is not correct. You need frequency mixing to actually measure THz waves, but you don't use frequency mixing to get THz lasing in GaAs QCLs.

    3. Re:No unit goof by grrrl · · Score: 1

      No, they aren't. It should read 30 - 300 um, which is the correct units quoted in the first line of the actual paper which I just dl'd from APL.

  22. Re:Room Temperature Semiconductor *Source* of T-Ra by Gilmoure · · Score: 1

    Well, I can take you as far as the interstate but after that, you're on your own.

    --
    I drank what? -- Socrates
  23. Even Higher Frequencies Possible? by Doc+Ruby · · Score: 3, Informative

    This THz frequency laser was made by building cheap and efficient IR lasers differing from each other by only a tiny wavelength difference, then using them to excite the active lasing material at their "beat frequency". That technique might be usable to generate ever-higher frequency lasers.

    For example, what about using two pairs of IR lasers, each pair resonating at a slightly different beat frequency? In fact a single "reference" IR laser could be split into two sources, with two different other sources each supplying their different frequencies into a THz laser of slightly different frequency. Then use those THz sources into an semiconductor active region which resonates at the beat frequency between the THz sources.

    That higher frequency result could be used as one of yet another pair, generating an even higher beat frequency. And since these steps up are made from thin film deposition, they could have such a hierarchical structure all contained in a very tiny device. Perhaps in a device at a scale that offers extremely high frequency lasers, manufactured and operating cheaply, without extra HW to maintain a useful beam.

    Perhaps a beam that could offer networks petabyte datarates. And perhaps, if the optical resonance junctions can be modulated by other photons, actual logic executing quickly, at low power.

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    make install -not war

    1. Re:Even Higher Frequencies Possible? by znerk · · Score: 1

      Interesting concept. Perhaps this could be used in computing to increase the available cpu speed, without necessarily having to invest in further silicon research? We're talking orders of magnitudes higher frequency than current cpus, yes?

      This is purely theoretical, and I actually have no idea what I'm talking about.

      --
      This work is licensed under a Creative Commons Attribution 3.0 Unported License.
    2. Re:Even Higher Frequencies Possible? by XHIIHIIHX · · Score: 1

      It makes the mind spin how quickly comcast would whip out the AUP on that connection.

    3. Re:Even Higher Frequencies Possible? by Anonymous Coward · · Score: 0

      I think you need to review the definition of "higher frequency". As used here your output wavelength is the difference in frequency between the two input lasers: Ft = abs(Fir1 - Fir2).

      Now if you try to repeat this trick you get a (potentially much lower) new frequency, probably in the GHz range. But as another poster has probably pointed out, this falls in the traditional radio frequency range and we already have very good (read 30%+ efficient) oscillators and amplifiers here. Lasers are usually fairly inefficient (CO2 lasers are exceptional at about 30%) to start with and I'm sure the non-linear optical element doesn't help at all.

      Still maybe there's a use for your cascaded beat filter somewhere else in the signal processing world.

    4. Re:Even Higher Frequencies Possible? by Doc+Ruby · · Score: 1

      It all depends on whether the engineers can make an all-optical computer. But it will all require further silicon research, as did this THz source device.

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      make install -not war

    5. Re:Even Higher Frequencies Possible? by Doc+Ruby · · Score: 1
      If the two lasers are very close in frequency, their beat frequency will be their difference, which will be a higher frequency than either of the two original frequencies. The THz frequencies make that beat frequency easier to be very high. I don't know why you think the beat frequency would be a low frequency.

      In fact the THz laser we're discussing here is generated by the beat frequency of two IR (lower frequency) lasers, which is why they're called "Quantum Cascade Lasers":

      To achieve the breakthrough and overcome the temperature limitations of current laser designs, the researchers engineered a room temperature mid-infrared Quantum Cascade Laser (QCL) that emits light at two frequencies simultaneously. The generation of Terahertz radiation occurs via the process of difference-frequency generation inside the laser material at room temperature at a frequency of 5 THz (equal to the difference of the two mid-infrared QCL frequencies).
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      make install -not war

    6. Re:Even Higher Frequencies Possible? by znerk · · Score: 1
      Well, like I said...

      I actually have no idea what I'm talking about. ;^)
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  24. and don't forget the F-Ray by WhiteDragon · · Score: 1

    Don't forget the F-Ray

    --
    Did you mount a military-grade, variable-focus MASER on an unlicensed artificial intelligence?
  25. F-Ray by Anonymous Coward · · Score: 0

    Ow!! My sperm!

  26. Come on guys, fix that headline by Lisandro · · Score: 0

    I read "Room Temperature Semiconductor of T-Rays" and thought "how can they create AC so high in frequency"?

  27. The top end of what's defined as radio. by Beryllium+Sphere(tm) · · Score: 1

    300 Ghz, I'm almost certain.

    1. Re:The top end of what's defined as radio. by Animats · · Score: 1

      ITU CVA 1005: "Radio waves are electromagnetic waves of frequencies arbitrarily lower than 3 000 GHz propagated without artificial guide". That's the international definition. There are currently discussions over whether this limit should be raised.

      The US FCC does not currently allocate spectrum above 300GHz, but there is already pressure on the FCC to act in that area.

  28. Prior art by 4thAce · · Score: 1

    Twinkle, twinkle, little bat
    How I wonder what you're at
    Up above the world you fly
    Like a T-ray in the sky.
    -- The Mad Hatter
    --
    Inventor of the LOLbalrog meme.
  29. t-ray phaser by Anonymous Coward · · Score: 0

    Vaporises the victim but leaves their clothes unscathed? What use is that? Do you need their clothes for a disguise or something?

  30. Can I get Superpowers from this? by pugugly · · Score: 1

    I can call my self Tee Man! Wearing My Tee-Shirt, I shall fight for truth, justice, and the almighty Buck! In my secret identity as Mr. (&*%^)$(^$)

    Ow - quit hitting me Mr. T - I would never have gone there!

    Pug

    --
    An Invisible Entity of Vast Power whose existence must be taken on faith alone: Liberal Media