It is known that classical electromagnetic radiation at a frequency in
resonance with energy splittings of atoms in a dielectric medium can be
described using the classical sine-Gordon equation. In this paper we quantize
the electromagnetic field and compute quantum corrections to the classical
results by using known results from the sine-Gordon quantum field theory. In
particular, we compute the intensity of spontaneously emitted radiation using
the thermodynamic Bethe ansatz with boundary interactions.Comment: 15 pages, one figure, uses harvmac and eps