QUANTUM PHENOMENA IN NONSTATIONARY MEDIA

The problem of electromagnetic-field quantization in time-dependent no nuniform linear nondispersive media is investigated. The explicit form ulas for the number of photons generated from the initial vacuum state due to the change in time of dielectric permeability of the medium ar e obtained in the case when the spatial and temporal dependences are f actorized. The concrete time dependences include adiabatic and sudden changes of permeability, the parametric resonance at twice the eigenfr equency of the mode, Epstein's symmetric and transition profiles, ''te mporal Fabry-Perot resonator,'' and some others. The upper and lower b ounds for the squeezing and correlation coefficients of the field in t he final state are given in terms of the reflection coefficient from a n equivilent potential barrier or the number of created quanta. The pr oblem of impulse propagation in a spatially uniform but time-dependent dielectric medium is discussed.