Is it possible to simulate the Dynamical Casimir Effect in a cavity? A simplified classical model

Considering the evolution of the classical electromagnetic field inside a cavity containing a thin slab with time-dependent conductivity and dielectric permittivity, an approximate analytical solution for an infinite set of coupled ordinary differential equations for the mode amplitudes is found under certain simplifying assumptions. According to this solution, an amplification of the initial field cannot be possible, unless the dielectric permittivity can become strongly negative.