Re: LASERS

[Ludwik Kowalski <KowalskiL@MAIL.MONTCLAIR.EDU>]

William Beaty wrote:

> What if each exited atom in the laser medium ABSORBED the incoming
> photon, and then re-radiated a pair of identical photons?  Rather than
> appealing to EM-fields to explain the triggered photon emission, or
> assuming that the proximity of a nearby photon can mysteriously trigger
> the atom to emit an identical one, we would then have a fairly sensible
> explanation (although perhaps not one which is correct in a QM sense.)

The atom is already excited. Your "model" assumes another excitation to a
higher level. The exactly matching levels would be rare among atoms and
molecules. Yet the phenomenon of "lasing" is rather common; about 30%
of elements, I my memory is correct, have been observed to "lase".

> If laser atoms absorb the stimulating photons, then they would emit photon
> pairs, and this photon-pairing phenomenon would be measurable.  I've
> seen mention of "photon pairing" in the literature on lasers.