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New Form of Matter Melds Lasers, Superconductors

sterlingda writes "Physicists at the University of Pittsburgh have demonstrated a new form of matter that melds the characteristics of lasers and superconductors. The work introduces a new method of moving energy from one point to another as well as a low-energy means of producing a light beam like that from a laser. The new state is a solid filled with a collection of energy particles known as 'polaritons' that have been trapped and slowed using a technique similar to that used to produce a Bose-Einstein condensate. The work is published in the May 18 issue of Science (subscription required to read beyond the abstract)."

2 of 113 comments (clear)

  1. Seriously -- Advantages? Applications? by sanman2 · · Score: 4, Interesting

    Okay, I found this other article about this discovery, and thought it was pretty good. It's worth a read:

    http://physicsweb.org/articles/news/11/5/17/1

    So this thing is like a BEC, but it's made of "excitons" (electron-hole pairs) plus the photons causing the excitation. But these "polaritons" are so short-lived, I'm wondering what this invention could be practically used for. They're calling it a "quasi-equilibrium" system, because it's more of a dynamic equilibrium.

    Could this "polariton condensate" be used to probe "quantum foam", or spacetime, or something? They've already said it's more energy efficient than a laser.
    Surely something this exotic must be able to confer on us some useful ability, that it would have some practical application -- even if only for research purposes.

    When I think of an exciton-photon combination as compared to electron inversion, then it reminds me of the difference between a turbine and a piston engine. This "polariton" thingy (exciton-photon combo) would be more efficient than the laser in a way that's analogous to how the turbine is more efficient than the piston explosion. I'd think that the key to maximizing its advantage is by stimulating the excitons with the highest energy photons possible. That way you're maximizing your energy savings from this more efficient process.

    Hmm... so maybe it might be useful for laser-confinement fusion after all. Maybe it could be used for laser-based rapid-manufacturing, etc.
    Whatever it is, you'd probably want it for a short-range application, due to the brief lifespan of the polaritons.

  2. Ordinary Lasers, But More Efficient by sanman2 · · Score: 4, Interesting

    Hi, I want to explain something here. This thing produces normal lasers, that are the same as the lasers we already know and love. The difference is that it can produce them using much less power input. The traditional method of electron population inversion requires more energy input for the amount of laser beam you get out. This new polariton method can make the same amount of laser for less energy inputted.

    For laser-confinement fusion, you'd want that kind of energy savings.
    Or SDI, or that ballistic missile interception laser mounted on that Boeing aircraft.

    I'm even wondering if those desktop particle accelerators based on laser-wakefield effect wouldn't also benefit.

    Anything that requires a high-power laser beam could benefit from this new polariton laser method. A turbine is already going round and round like a polariton, and is distinct from the discrete reciprocating motion of a piston, or the population inversion of electrons.