DETAILED BALANCE AND ENTROPY FOR ATOMS IN SQUEEZED VACUUM

It is shown that the Principle of detailed balance is not obeyed in bo th systems of a single 2-level atom and the two-atom Dicke model inter acting with a broad band squeezed vacuum held. Examination of the Bolt zmann-Gibbs entropy shows that the stability of either system depends on the initial conditions, In particular, the two-atom system is unsta ble even for initially ground state condition, unlike the thermal held driven case.