Analogue model for controllable Casimir radiation in a nonlinear cavity with amplitude-modulated pumping: generation and quantum statistical properties

摘要

We present and investigate an analogue model for controllable photon generation via the dynamical Casimir effect (DCE) in a cavity containing a degenerate optical parametric amplifier (OPA), which is pumped by an amplitude-modulated field. The time modulation of the pump field in the model OPA system is equivalent to a periodic modulation of the cavity length, which is responsible for the generation of the Casimir radiation. By taking into account the rapidly oscillating terms of the modulation frequency, the effects of the corresponding counter-rotating terms (CRTs) on the analogue Casimir radiation clearly emerge. We find that the mean number of generated photons and their quantum statistical properties exhibit oscillatory behaviors, which are controllable through the modulation frequency as an external control parameter. We also find that the time-modulated pumping may lead to the recently predicted phenomenon, the so-called "anti-DCE," in which pair photons can be coherently annihilated. We show that the Casimir radiation exhibits quadrature squeezing, photon bunching, and super-Poissonian statistics, which are controllable by modulation frequency. We also calculate the power spectrum of the intracavity light field. We find that the appearance of sidebands in the spectrum is due to the presence of the CRTs. (C) 2015 Optical Society of America