Controlling stationary one-way steering via thermal effects in optomechanics

Abstract

Quantum steering is a kind of quantum correlations stronger than entanglement but weaker than Bell-nonlocality. In an optomechanical system pumped by squeezed light and driven in the red sideband, we study-under thermal effects-stationary Gaussian steering and its asymmetry of two mechanical modes. In the resolved sideband regime using experimentally feasible parameters, we show that Gaussian steering can be created by quantum fluctuations transfer from the squeezed light to the two mechanical modes. Moreover, one-way steering can be observed by controlling the squeezing degree or the environmental temperature. A comparative study between Gaussian steering and Gaussian Rényi-2 entanglement of the two considered modes shows on one hand that both steering and entanglement suffer from a sudden death-like phenomenon with early vanishing of steering in various circumstances. On the other hand, steering is found stronger than entanglement, however, remains constantly upper bounded by Gaussian Rényi-2 entanglement, and decays rapidly to zero under thermal noise. 1

Entanglement and Asymmetric Steering Between Distant Magnon and Mechanical Modes in an Optomagnonic‐Mechanical System

“…[ 50 ] We note that the optimal situation for transferring the squeezed light from the driving field to the magnon mode and phonon mode can be achieved when the frequency of squeezing is resonant with the two cavities ($$\omega _s=\omega _{1,2}$$). [ 46,51,52 ] The input noise of the magnon mode and phonon mode $$O_{\textrm {in}}$$ ($$O=m,b$$) are zero mean, and the correlations are as follows $$\begin{eqnarray} \langle O_{\textrm {in}}(t)O^\dag _{\textrm {in}}(t^{\prime }) \rangle &=&(n_{O}+1)\delta (t-t^{\prime }) \nonumber\\ \langle O^\dag _{\textrm {in}}(t)O_{\textrm {in}}(t^{\prime })\rangle &=&n_{O}\delta (t-t^{\prime }) \end{eqnarray}$$where $$n_O=[\text{exp}(\frac{\hbar \omega _O}{k_BT})-1]^{-1}$$ is the mean equilibrium thermal magnon (phonon) number, with T and $$k_B$$ being the environmental temperature and Boltzmann constant, respectively.…”

“…[50] We note that the optimal situation for transferring the squeezed light from the driving field to the magnon mode and phonon mode can be achieved when the frequency of squeezing is resonant with the two cavities (𝜔 s = 𝜔 1,2 ). [46,51,52] The input noise of the magnon mode and phonon mode O in (O = m, b) are zero mean, and the correlations are as follows…”

One-way steering of the optical fields with respect to the low-Q cavity via the thermal noise

“…It is obvious that the thermal noise plays a negative role in entanglement manipulation in the above schemes and it degrades the degree of entanglement and even leads to the sudden death of entanglement. We note that the influence of thermal noise on bipartite and tripartite quantum steering has recently been investigated in a optom echanical system [52,53].…”

Enhanced Entanglement and Controlling Quantum Steering in a Laguerre–Gaussian Cavity Optomechanical System with Two Rotating Mirrors

“…In addition to its fundamental physical importance, quantum steering has significant practical applications, such as high-fidelity heralded teleportation using minimally entangled yet steerable resources [21] and the quantum subchannel discrimination problem. [22] In recent years, many of the studies have focused to achieve these goals in many optomechanical [23][24][25] and in magnomechanical systems. [26][27][28] This is because of advancements in present-day technology that the most promising feature of quantum steering, one-way steering, has been experimentally demonstrated.…”