Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!


Forgot your password?

Manipulating Heat Like Light 82

An anonymous reader writes "A new technique allows allows 'thermocrystals' to be created that can manipulate heat (a vibration of the atomic lattice of a material). Predicted manipulations include the ability to selectively transmit, reflect or concentrate heat much like light waves can be manipulated by lenses and mirrors. 'Heat differs from sound, he explains, in the frequency of its vibrations: Sound waves consist of lower frequencies (up to the kilohertz range, or thousands of vibrations per second), while heat arises from higher frequencies (in the terahertz range, or trillions of vibrations per second).' Applications range from better thermoelectric devices to switchable heat insulating/transmitting materials (abstract). Perhaps this will result in better cooling/heating mechanisms or more efficient engines."
This discussion has been archived. No new comments can be posted.

Manipulating Heat Like Light

Comments Filter:
  • by Anonymous Coward on Friday January 11, 2013 @07:21PM (#42563175)

    Maxwell's Demon?

    • by radtea ( 464814 ) on Friday January 11, 2013 @08:17PM (#42563611)


      They first have to select specific wavelengths and then--it sounds like--frequency-shift them.

      To call this "heat" is a deliberately misleading statement designed to elicit precisely the question you are asking, as that will attract much more of our most limited resource--attention--to this otherwise interesting but essentially esoteric work.

      "Heat" in ordinary parlance is constituted by vibrational modes that obey the principle of equipartition, which this "heat" manifestly does not.

      • Terahertz [wikipedia.org] technology is an interesting research topic, but it is not about heat.
      • Re: (Score:2, Funny)

        by Anonymous Coward

        So essentially it's now ok to overload semantics in scientific writings ?!
        I just invented* a safe** and practical*** form of cold-fusion****.

        * stole
        ** for non sentient life forms outside of solar system
        *** for the purpose of filling my bank account
        **** relative to the sun, not so much to the atmosphere...

        This is precisely why C++ sucks Afro-Caucasian***** balls.

        ***** chocolate milk ice cream.

      • by guises ( 2423402 )
        So... if I select out a certain wavelength of light then it isn't proper to call it light anymore? Come on, if you're using common parlance then "heat" really just means "thermal energy" anyway. This may be a little esoteric, but I could see this developing into a lot of potential applications.

        I'll grant that this isn't breaking news for most people, but as science reporting goes this is pretty good. It's better than another fad diet or fish oil bullshit story.
  • by brentonboy ( 1067468 ) on Friday January 11, 2013 @07:31PM (#42563257) Homepage Journal

    I wonder if you could use this to concentrate low levels of heat and generate electricity from it. Not only would you be able to get energy out of (almost) nothing, (albeit, probably not much), but you could cool an area without producing a lot of waste heat.

    • by jonbryce ( 703250 ) on Friday January 11, 2013 @08:17PM (#42563609) Homepage

      No, because it would violate the 2nd law of thermodynamics.

      • Re: (Score:2, Funny)

        by brentonboy ( 1067468 )

        No, because it would violate the 2nd law of thermodynamics.

        Does the 2nd law of thermodynamics not apply to a steam generator?

        • Concentrating heat and then using it to do work violates the second law of thermodynamics.

          If you can concentrate heat, it must be in a setup that would makes a thermal machine not work.

          • You can concentrate heat and use it to run a thermal machine. However it will require more work to concentrate the heat than you will get out of the thermal machine.

        • Yes, in that a steam generator is able to capture energy from the transfer of heat from a hot area to cold area and uses it to do work.

      • It's only a "law" because we do not yet know how to break it.

        I, for one, look forward to the day (year, century...) when we decide that it's an obsolete principle. Until we actually know all the rules of the game, all the interactions, all the api of the universe... we cannot know that anything is truly a "law of physics". We can speculate, postulate, investigate, narrow-in-on, or disprove, but never really affirm.

        (Which is not to say that this specific mechanism shows any promise, just that some mechanis

    • You can imagine a setup with a black body radiator and a theoretical lense and attempt to focus the black body radiation to heat another object to a higher temperature than the original black body. And it is not possible. The laws of thermodynamics apply of course but they don't explain the why. If you go through the motions and try to calculate how hot you can get the second object you find you can't get it hot enough. You can't focus the radiation to make it hotter.

  • by snadrus ( 930168 ) on Friday January 11, 2013 @07:37PM (#42563283) Homepage Journal
    How did this one get missed? Fusion's biggest problem is heat management.
    Thermal Diodes: Hook this to a solar collecting sterling engine for a considerable performance boost.
    That sounds like passive Heating & Air conditioning. Maybe society will use technology to reduce its power consumption overall.
    • by wontie ( 2368458 )
      This. This is huge! Well, ... assuming it can be made to work, and at a larger scale, the possibilities to improve energy efficiency are intriguing. Of course, the military might have an interest here too: could it be used to cloak heat signatures? It sounds like a meta material to me.
      • A thermal cloaking effect was our first thought here. It's a cast iron bitch to try and hide a tank even with the thermal cloaking blankets today. I'd have to read (and think) so more before I can determine naval applications. [Naval background here.]
      • by dywolf ( 2673597 )

        my first thought was a "heat laser". the perfect solution to heat dissipation in space....turn it into a weapon!

    • Or even spaceships, heat dissipation can be a major issue with long term presences in space.

  • by Anonymous Coward
    This is just EM radiation that at our temperature and materials just happens to turn into heat easily.
  • by sandytaru ( 1158959 ) on Friday January 11, 2013 @07:51PM (#42563367) Journal
    These crystals aren't heat sinks. The MIT lab is creating a "heat" that is actually just really fast sound. This can then be manipulated with their special thermocrystals. Now, if they can create a way to turn normal waste heat into this "fast sound" heat, we'll open up a wealth of practical applications.
    • Yes, Just imagine it! Ultrasonic Welding of Plastics!
    • I presume we are then talking about phonon manipulation. Which is pretty cool (sorry for that pun) but at the moment I can't see a lot of applications. Should be able to do lots of interesting photon like things but much slower. Useful if you want to embed logic in a solid material.

  • by icebike ( 68054 ) on Friday January 11, 2013 @07:57PM (#42563417)

    From TFA:

    The crystals could also be used to create thermal diodes: materials in which heat can pass in one direction, but not in the reverse direction. Such a one-way heat flow could be useful in energy-efficient buildings in hot and cold climates.

    Other variations of the material could be used to focus heat — much like focusing light with a lens — to concentrate it in a small area. Another intriguing possibility is thermal cloaking,

    Some of the speculative uses seem pretty interesting. To date it is only 40% efficient at some of these tasks, but that's not bad for starters.

    These things sound like beginnings of heat circuitry components. The method involves making alloys of silicon that incorporate nanoparticles of germanium in a particular size range, and layering these thin films. If they can find a dynamically controllable switch structure you could build most of the necessary components for simple circuits.

    Then you run into this sentences from TFA:

    Heat also spans a wide range of frequencies, he says, while sound spans a single frequency.

    Wow. Journalism student I'm guessing?

  • Sound is pressure waves. Heat, or more accurately, infrared, is electromagnetic radiation.

    They are so vastly different, far beyond just frequency, that I'm not sure what the person who wrote the summary is smoking. :)

    • You need to take your thermodynamic classes again.

      Heat and infrared radiation are two very different things.

      • by gd2shoe ( 747932 )
        Yes indeed. Heat has more in common with sound than it does with light. (Not that they're the same.)
  • One of the major problems with creating extremely powerful fan-less processors for mobile devices is heat. Heat problems increase to a square of scale variations when miniaturizing circuitry. If control of heat can be directed to increase the flow of heat away from NEMS and microchips adequately, we could see mobile devices that could compete with the most powerful current desktop processor.
  • ...but is this a step towards a working Thermal Discouragement Beam? [wikia.com]
  • Usually the main problem with press release science is that it has nothing to do with the real science behind it. Probably, there's an MIT professor embarrassed to show up to colloquia right now.

    This press release is talking about acoustic metamaterials. The scientific description in the press release is bad, very bad, but one thing they got dead wrong is that this is not new.

  • Very interesting. Dont you think It always sounded weird when you were in class and the teacher claimed Energy is partially converted partially lost as heat. Certanly these thermocrystals should be kept an eye on. For funding, research and peer finding please refer to the non-profit Aging Portfolio.

To do two things at once is to do neither. -- Publilius Syrus