Enhancing quantum correlations in an optomechanical system via cross-Kerr nonlinearity

Abstract

In this work, we theoretically study the quantum correlations present in an optomechanical system by invoking an additional cross-Kerr coupling between the optical and mechanical mode. Under experimentally achievable conditions, we first show that a significant enhancement of the steady-state entanglement could be achieved at a considerably lower driving power, which is also extremely robust with respect to system parameters and environmental temperature. Then, we employ Gaussian quantum discord as a witness of the genuine quantumness of the correlation present in the system and discuss its dependence on the cross-Kerr nonlinearity.

Generating sustained coherence in a quantum memory for retrieval at the times of quantum revival

“…A typical quantum optomechanical system consists of a Fabry-Perot cavity with one of the movable mirrors acting as a mechanical oscillator [10]. The optical mode trapped inside the Fabry-Perot cavity is coupled to the mechanical mode via a generic coupling represented by g 0 [13]. The optical mode and the mechanical mode have the frequencies ω c and ω m , respectively.…”

“…To choose the parameters for our system that show experimental consistency, we follow the work done by [13]. They numerically illustrated the effect of cross-Kerr coupling on the steady-state behavior and stability condition of the optomechanical system by considering the experimentally accessible frequencies of optical and mechanical modes as ω c = 2π × 370 THz and ω m = 2π × 10 MHz respectively.…”

“…Quantum state formation through system anharmonicities as well as decoherence due to interactions with the environment in terms of Wigner current was studied by Braasch et al [12]. Chakraborty et al [13] presented a scheme to enhance the steady-state quantum correlations in an optomechanical system by incorporating an additional cross-Kerr-type coupling between the optical and the mechanical modes. He et al [14] proposed a dynam-ical approach for quantum memories using an oscillatorcavity model to overcome the known difficulties of achieving high quantum input-output fidelity with long storage times.…”

Nonclassicality via the Superpositions of Photon Addition and Subtraction and Quantum Decoherence for Thermal Noise

“…In most of the realistic scenarios, the more general environment is the coexistence of two or more noise sources that causes more complicated but practical decoherence behaviors. [20] Besides, nonlinear interactions of light in a medium, such as noisy Kerr interaction, [21][22][23] nonlinear dissipative oscillator, [24] and parametric down conversion at finite temperature, [25,26] are widely explored because highly nonlinear systems have the applications of importance in many aspects (e.g., Bose-Einstein condensates, cold atoms, and light propagation) of atomic and molecular physics and quantum physics. Overall, it is pretty necessary to find a series of nonclassical light fields that have better robustness against the decoherence and minimize the effect of the noise on their nonclassicality and entanglement.…”

Enhancement of few-photon optomechanical effects with cross-Kerr nonlinearity

“…With this method, the singlephoton optomechanical coupling can be enhanced several orders of magnitude. Meanwhile, this circuit also creates a cross-Kerr interaction [53,[58][59][60] between the optical mode and the mechanical mode, and the magnitude of the cross-Kerr interaction might be a fraction of the single-photon optomechanical coupling strength. Based on the fact that the original motivation of the proposal based on the superconducting circuit is to enhance the single-photon optomechanical coupling and to further realize the few-photon optomechanical tasks, it is therefore natural to ask the question: what is the effect of the additional cross-Kerr interaction on the few-photon optomechanical tasks such as the photon blockade and the generation of the Schrödinger cat states?…”