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Polariton BEC, Polariton Laser - Applications?

  1. May 19, 2007 #1

    This latest announcement on the development of something resembling a BEC using polaritons seems interesting:



    So I'd like to know what the implications of this development are. Could this "polariton BEC" be used in further experiments to probe matter? Could it be used as a springboard to make more important discoveries, and if so, how?

    Are there any possible practical applications of this development? The announcement says that this "polariton BEC" could generate laser output in a more energy-efficient way than lasers achieved through conventional population inversion of electrons. The "polariton BEC" can apparently also be achieved at temperatures somewhere between liquid nitrogen and room temperature, which sounds more cost-effective.

    Could it perhaps then be used to generate high-energy lasers more efficiently, and thus be of assistance in applications like laser-confinement fusion, for example? Or maybe directed energy weapons?

    What are the limitations and constraints on this technology?
  2. jcsd
  3. May 24, 2007 #2
    Interesting, Sanman. I can't tell you anything, but thanks, because I followed your links and more, then printed myself some interesting bedtime reading about magnons, phonons, polaritons, excitons, and exciton-polaritons in Copper Oxide. I don't know how relevant this was in your second link:

    "..Nonetheless, there may still be doubts whether Snoke's system is a BEC in the conventional sense, because polaritons have such a short lifetime that the system can only reach a quasi-equilibrium.."
  4. May 24, 2007 #3
    polariton lasers

    Hi Voltage,

    Well, this "new form of matter" seems to be matter kept in an excited state, due to a resonant cavity. We're told from classical physics and chemistry that the closer a system is to its equilibrium point in relation to a certain reaction, the more efficiently that reaction proceeds. So in this case, the reaction in question is the conversion between electron energy and photon energy. Because the "new matter" is in a quasi-equilibrium in this respect, it should facilitate a more efficient production of laser light. Supposedly 10 to 100 times more efficiently, they claim.

    I'm wondering then if this great energy savings could make laser-confined fusion more energy efficient and bring it closer to the breakeven point. I'm also wondering if directed energy weapons could also similarly benefit. Furthermore, there are newer methods of rapid manufacturing such as Selective Laser Sintering and Selective Laser Melting which use high-energy lasers to melt powdered material into fully-functional parts/objects. Perhaps this too could also benefit from the energy savings of a polariton laser. But certainly, DVD players/recorders having more efficient lasers with even lower power-consumption would also be nice too.


    I'm just curious to know what people think about this. To me, it sounds like a fundamental breakthrough of great technological importance, especially if it can work at or near room temperature.
    Last edited: May 24, 2007
  5. May 29, 2007 #4
    Also, if this new Polariton BEC is in quasi-equlibrium with respect to photoelectric conversion, then does it mean it could somehow be used to harvest photoelectric energy more efficiently?

    For example, could it generate an electric current from extremely low levels/wavelengths of light, which an ordinary semiconductor might not be able to use? Could a Polariton BEC become an ultra-efficient photoelectric cell?
  6. Jun 7, 2007 #5
    Nanotubes & Excitons

    Here's a related news article:


    Could the unique properties of the nanotubes with respect to exciton longevity make them good candidates for creating polariton BECs and ultra-efficient polariton lasers?
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