Dynamical Casimir effect for TE and TM modes in a resonant cavity bisected by a plasma sheet

Parametric photon creation via the dynamical Casimir effect (DCE) is evaluated numerically, in a three-dimensional rectangular resonant cavity bisected by a semiconductor diaphragm (SD), which is irradiated by a pulsed laser with frequency of GHz order. The aim of this paper is to determine some of the optimum conditions required to detect DCE photons relevant to an experimental detection system. We expand upon the thin plasma sheet model [ M. Crocce et al. Phys. Rev. A 70 033811 (2004)] to estimate the number of photons for both transverse electric (TE) and transverse magnetic (TM) modes at any given SD position. Numerical calculations are performed considering up to 51 intermode couplings by varying the SD location, driving period and laser power without any perturbations. It is found that the number of photons created for TE modes strongly depends on SD position, where the strongest enhancement occurs at the midpoint (not near the cavity wall); while TM modes have weak dependence on SD position. Another important finding is the fact that significant photon production for TM₁₁₁ modes still takes place at the midpoint even for a low-laser power of 0.01 μJ/pulse, although the number of TE₁₁₁ photons decreases almost proportionately with laser power. We also find a relatively wide tuning range for both TE and TM modes that is correlated with the frequency variation in the instantaneous mode functions caused by the interaction between the cavity photons and conduction electrons in the SD excited by a pulsed laser.