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

Abstract

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 a novel experimental detection system. We expand upon the thin plasma sheet model [Crocce et al., Phys. Rev. A 70 033811 (2004)] to estimate the number of photons for both TE and TM modes at any given SD position. Numerical calculations are performed considering up to 51 inter-mode 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 of the instantaneous mode functions caused by the interaction between the cavity photons and conduction electrons in the SD excited by a pulsed laser.

Influence of periodically modulated cavity field on the generation of atomic-squeezed states

“…For example, it has been shown in Ref. [13] that using a semiconductor plasma mirror [45] with Q of the order 10 3 it is possible to achieve the so-called threshold condition for generation of squeezed photons. Therefore, we expect that a beam of Rydberg atoms interacting with the field mode of this cavity will be able to produce significant amount of atomic squeezing.…”

Photon creation in a resonant cavity with a nonstationary plasma mirror and its detection with Rydberg atoms

“…The Dirichlet boundary condition is adopted at x = 0,L with sin k[L − δ + ξ (t)] = 0, corresponding to the case of transverse electric (TE) modes. The case of transverse magnetic (TM) modes can be treated in a similar way by adopting m 2 (x,t) = [(∂n e /∂x)e 2 /(k 2 ⊥ m * )] [23].…”

“…The present approach on the fixed basis, however, does not work effectively in an extreme situation where the mode functions are largely deformed in time with |δω k (t)| ∼ ω 0 k . In such a case, the instantaneous-mode approach is rather suitable, though the deformation of the mode functions cannot be treated perturbatively [23]. Anyway, as seen in the following, a reasonable deformation to induce |δω k (t)|/ω 0 k ∼ 0.01 − 0.1 is sufficient to create a significant number of photons for detection with atoms.…”

“…involving the average shift of the frequency δω [18,23] rather than the naive condition = 2ω 0 . If = 2ω 0 is taken with = − δω , the squeezing rate χ is significantly reduced, even possibly becoming imaginary with n γ (t) < ∼ 1 oscillating as sin 2 |χ |t.…”

“…We particularly intend to examine the experimental realization of DCE with a plasma mirror of a semiconductor slab [15,23]. In Sec.…”