Physics

Dr. Vivek M. Vyas
The Institute of Mathematical Sciences, Chennai

Half a century back, Dicke studied a model of a collection of two level atoms interacting with a single cavity mode. It was found that when the atoms are in what is called the Dicke state, the photon
emission probability is significantly larger than the spontaneous
emission probability. This phenomenon was called superradiance. In
this talk, it will be shown that such a superradiant state of photons
is actually a coherent state. The relation between Bose-Einstein
condensation, spontaneous symmetry breaking and superradiance in
photonic systems will be shown. It will be shown that superradiant
emission of photons from Dicke states is fundamentally different from
spontaneous and stimulated emission phenomena.