Manipulation and enhancement of asymmetric steering via interference effects induced by closed-loop coupling

Abstract

We present a phase control method for a general three-mode system with closed-loop in coupling that drives the system into an entangled steady state and produces directional steering between two completely symmetric modes via quantum interference effects. In the scheme, two modes are coupled with each other both by a direct binary interaction and by an indirect interaction through a third intermediate damping mode, creating interference effects determined by the relative phase between the two physical interaction paths. By calculating the populations and correlations of the two modes, we show that depending on the phase, two modes can be prepared into an entangled steady state with asymmetric and directional steering even if they possess completely symmetric decoherence properties. Meanwhile, entanglement and steering can be significantly enhanced due to constructive interference, and thus more robust to thermal noises. This provides an active method to manipulate the asymmetry of steering instead of adding asymmetric losses or noises on subsystems at the cost of reducing steerability. Moreover, we show that the interference effects can also enhance and control the correlations between other pair of modes in the loop with opposite phase dependent behavior, indicating monogamy constraints for distributing correlations among multipartite. The present model could be applied in cavity optomechanical systems or in antiferromagnets where all components can mutually interact.

Dissipative generation of significant amount of photon-phonon asymmetric steering in magnomechanical interfaces

“…The a → b steering G A will be greater than the b → a steering G B only if both the conditions of larger γ and smaller nb are satisfied (e.g., γ = 0.07 and nb = 0), otherwise, G B ≥ G A . The results enriches the earlier studies [69][70][71][72], where only the mode with larger dissipation rate can be steered by the other one. Besides, significant amount of two-way and one-way asymmetric quantum steering between the photon and phonon modes can be obtained with even equal dissipation (e.g., κ a = γ = 0.02).…”

Certification and applications of quantum nonlocal correlations

“…Given that it is so rare in the context of quantum correlations, this asymmetry is an important property and promises interesting applications [85]. The asymmetry has been realized in different scenarios, in which there is also evidence of manipulation of this asymmetry [58,[86][87][88][89][90][91][92][93]. In this way, the asymmetry of steering provides important advantages for applications, such as in QKD, where now protocols in which we only require one party to be trustworthy are realizable [94], as well as permitting different characteristics that improve the security of quantum teleportation [95].…”

Some Measurement-Based Characterizations of Separability of Bipartite States

“…As an intermediary property between Bell nonlocality and entanglement, EPR steering was first observed by Schrödinger [2] in the context of the well-known EPR paradox [1,[20][21][22]. It is also is an important resources in quantum information and then has been recently discussed, please refer to [17,[23][24][25][26][27][28][29][30][31]. Especially, mathematical definitions of Bell nonlocality and EPR steerability of bipartite states were proposed and their characterizations were given in [17] by Cao and Guo. Although entanglement was first recognized as the characteristic trait of quantum mechanics [1], its role has been debated since it does not capture all the quantum features of a quantum system [32][33][34].…”