Nonlinearity enhancement in optomechanical systems

Abstract

The nonlinearity is an important feature in the field of optomechanics. Employing atomic coherence, we put forward a scheme to enhance the nonlinearity of the cavity optomechanical system. The effective Hamiltonian is derived, which shows that the nonlinear strength can be enhanced by increasing the number of atoms at a certain range of parameters. We also numerically study the nonlinearity enhancement beyond the effective Hamiltonian. Furthermore, we investigate the potential usage of the nonlinearity in performing a quantum nondemolition (QND) measurement of the bosonic modes. Our results show that the present system exhibits synchronization, and the nonlinear effects provide us an effective method in performing QND.

Bistability and Entanglement of a Two-Mode Cavity Optomechanical System

“…As we have shown in [41], the entanglement between two cavity modes only can exit for a span of time; finally, there is no steady-state entanglement for the interaction of beam split form. Thus, we can safely summarized that although the two cavity modes exhibit cross Kerr nonlinearity mediated by [35,36], each of the two cavity modes entangle with the mechanical mode separately, whereas no entanglement is observe between the two optical modes.…”

“…In this paper we show that the regime in term of pumping amplitude can be adjusted by tuning the frequency of pumping field. Although there is a kind of correlation between the two modes of the cavity field due to common interaction with the mechanical mode [36], the two modes do not exhibit steady state entanglement, while each of the two modes entangle with mechanical mode separately.…”

“…The first two terms of (1) describe the free energy of the two modes of the optical cavity as well as the mechanical oscillators with frequencies ω cj and ω m , respectively. The third term (the same as in [35,36]) represents the coupling between the nonpolarized two-mode fields and the mechanical mode resonator with radiation-pressure coupling g = 1 L ω c 1 ω c 2 2Mω m . For the two modes cavity optmechanical system, the coupling between the fields and the mechanical mode has been shown in [37].…”

“…Introducing atomic coherence into the two modes optomechanical system, our group in Ref. [36] put forward a scheme to enhance and modulate the photon-photon and photon-phonon cross-Kerr nonlinearity by employing atomic coherence. However, the bistable behavior and the entanglement properties in the two modes optomechanical system, shown in Fig.…”

Controlling photon transport in the single-photon weak-coupling regime of cavity optomechanics

“…The nonlinear interaction between optical and mechanical modes arising from radiation pressure force in optomechanical (OM) systems exhibit a lot of interesting nonlinear effects such as photon (phonon) blockade [16,17], optomechanical induced transparency [18,19] and Kerr nonlinearity [20,21]. Cavity optomechanics has received significant attention both in fundamental experiments [22,23] and sensing applications [24,25].…”