Theory of the dynamical Casimir effect in nonideal cavities with time-dependent parameters

Abstract

This is a brief review of the recent progress in the theory of dynamical (non-stationary) Casimir effect in non-ideal cavities and of existing proposals to observe this effect in a laboratory, with an emphasis on the experiment which is under preparation in the University of Padua. The main idea of this experiment is to simulate periodical displacements of the cavity wall by periodical strong changes of conductivity of a thin semiconductor slab illuminated by picosecond laser pulses. In this connection the theory of quantum damped oscillator with arbitrary time dependence of the frequency and damping coefficient has been developed in order to take into account intrinsic losses in the semiconductor slab due to a finite conductivity during the intermediate part of the excitation-recombination cycle. The influence of different parameters, such as the diffusion and mobility coefficients of carriers, surface recombination velocity, absorption coefficient of laser radiation, thickness of the slab and geometry of the cavity, is analysed. Analytical and numerical evaluations show that under realistic experimental conditions, several thousand of quanta of EM field (Casimir photons) could be produced from the initial vacuum state in a high-quality cavity at the lowest resonance frequency 2.5 GHz. © 2008 IOP Publishing Ltd.