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Light emission/absorption revisited by chemical thermodynamics

  1. Nov 26, 2008 #1

    using the words of chemical thermodynamics could we say that stimulated emission of light is "catalysed" by incident photons, as well as absorption ?

    In that way, does it mean that there is a kind of "activation energy" in the emission process ?

    Without incident photon, spontaneous emission needs some help to jump to a lowest level (the needed energy is coming from the vaccuum). So, an incident photon should act as a "catalysor" which is able to attenuate the barrier. The stimulated emission process is "catalysed" by the external field. This can be quickly demonstrated using thermodynamics of black body and the "cinetic" relation between the Einstein's coefficients.

    Could someone help me verifying this point of view (if it is a correct one) ? What possible link with quantum electrodynamics ?

  2. jcsd
  3. Nov 27, 2008 #2
    I have got an answer to my question (from A.KASSLER lab. in Paris) : there is no activation energy for the spontaneous emission. There is an exponential decay as usual when a level is coupled to a continuum. Vacuum fluctuations are of course involved in the process but standard radiation damping plays an important role too.
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