arXiv:1104.4145 · Physical Review A

Quantum optomechanics in the bistable regime

Roohollah Ghobadi, Alireza Bahrampour, Christoph Simon

Published Sep 22, 2011• 101 citations

Abstract

We study the simplest optomechanical system with a focus on the bistable regime. The covariance matrix formalism allows us to study both cooling and entanglement in a unified framework. We identify two key factors governing entanglement; namely, the bistability parameter (i.e., the distance from the end of a stable branch in the bistable regime) and the effective detuning, and we describe the optimum regime where entanglement is greatest. We also show that, in general, entanglement is a nonmonotonic function of optomechanical coupling. This is especially important in understanding the optomechanical entanglement of the second stable branch.

DOI: 10.1103/physreva.84.033846

Related papers

Optomechanical entanglement in the presence of laser phase noise

Roohollah Ghobadi, Alireza Bahrampour, Christoph Simon

We study the simplest optomechanical system in the presence of laser phase noise (LPN) using the covariance matrix formalism. We show that for any LPN model with a finite correlation time, the destructive effect of the phase noise is especially strong in the bistable regime. This explains why ground-state cooling is still possible in the presence of phase noise, as it happens far away from the bistable regime. We also show that the optomechanical entanglement is strongly affected by phase noise.

arXiv:1106.0788Physical Review ADec 12, 201130 citations

Quantum Optomechanics in the Bistable Regime

Roohollah Ghobadi, Dustin Kleckner, Brian J. Pepper +3 more

We have studied the simplest optomechanical system close to and in the bistable regime. We find that Optomechanical entanglement is particularly strong in this regime for large enough detuning. The robustness of entanglement against temperature is also studied.

International Conference on Quantum InformationJan 1, 20112 citations

Multimode strong-coupling quantum optomechanics

Hyojun Seok, Lukas F. Buchmann, Ewan M. Wright +1 more

We study theoretically the dynamics of multiple mechanical oscillators coupled to a single cavity field mode via linear or quadratic optomechanical interactions. We focus specifically on the strong-coupling regime where the cavity decays much faster than the mechanical modes, and the optomechanical coupling is comparable to or larger than the mechanical frequency, so that both the optical and mechanical systems operate in the deep quantum regime. Using the examples of one and two mechanical oscillators, we show that the system can classically exhibit bistability and bifurcations, and we explore how these manifest themselves in interference, entanglement, and correlation in the quantum theory, while revealing the impact of decoherence of the mechanical system due to cavity fluctuations and coherent driving.

arXiv:1309.7134Physical Review ADec 30, 201351 citations

Optical bistabilities in cavity optomechanics

Yasser Amoun Sharaby, Ibrahim Mohamed Kandil, Shoukry S. Hassan +1 more

In this review, we will focus on optical bistability and the condition for its occurrence in cavity optomechanics. We study different optomechanical systems (basic optomechanical systems and hybrid optomechanical systems). we derived an equation that could predict the behavior of the system either bistable, transistor or monostable for each system considered depending on the value of its parameters. This equation is derived using analytical study for functional relation between the incident intensity field as a function of the optical cavity field intensity. Investigating the relation between any physical measurable quantity in the optomechanical system against the incident field intensity and its dependency on fundamental optical cavity field against the incident field intensity. Finally, studying the effects of integrating two types of atomic media into the optomechanical system, and tunability it could provide to the optomechanical system, each medium is separately studied. The atomic medium also tends to squeeze the domain of the bistability within the system relative to the basic optomechanical system

Frontiers in Scientific Research and TechnologyAug 26, 20242 citations

Measure of general quantum correlations in optomechanics

Mohamed Amazioug, Mostafa Nassik, Nabil Habiballah

In this paper, we analyze nonclassical correlations between bipartite states in two optomechanical systems. The first system (Sec. 2) consists of two nanoresonators spatially separated by broadband squeezed light, where each cavity has a fixed mirror and a movable one. The second system (Sec. 3) is an atom-optomechanical system consisting of an atomic ensemble placed inside an optical nanoresonator with a vibrating mirror. For both optomechanical systems, we give the Hamiltonian and the explicit expression of covariance matrix leading to the quantum equations describing the dynamic evolution of the system. Then, the nonclassical correlations are quantified using the logarithmic negativity and Gaussian quantum discord. We propose also a scheme for examining the evolution of Gaussian quantum steering and its asymmetry in each system. We show that the entanglement of the two mechanical modes is very strongly related to the parameters characterizing the environment where the movable mirrors evolve, in particular the squeeze parameter, the optomechanical cooperativity and thermal bath temperature.

International Journal of Quantum InformationAug 1, 201819 citations

Nonlinearly induced entanglement in dissipatively coupled optomechanical system

Wen-Quan 文全 Yang 杨, Xuan Leng, Jiong 泂 Cheng 程 +1 more

Nonlinearly induced steady-state photon–phonon entanglement of a dissipative coupled system is studied in the bistable regime. Quantum dynamical characteristics are analysed by solving the mean-field and fluctuation equations of the system. It is shown that dissipative coupling can induce bistable behaviour for the effective dissipation of the system. Under suitable parameters, one of the steady states significantly reduces the dissipative effect of the system. Consequently, a larger steady-state entanglement can be achieved compared to linear dynamics. Furthermore, the experimental feasibility of the parameters is analysed. Our results provide a new perspective for the implementation of steady-state optomechanical entanglement.

Chinese Physics BApr 12, 20243 citations