Quantum synchronization and correlation in bidirectionally and unidirectionally coupled optomechanical oscillators

TL;DR

This paper explores quantum synchronization and correlations in optomechanical oscillators with different coupling topologies, revealing topology-dependent behaviors like Arnold tongue patterns and quantum synchronization blockade.

Contribution

It introduces a comparative analysis of bidirectional and unidirectional couplings in optomechanical oscillators, highlighting topology-specific quantum synchronization phenomena.

Findings

Bidirectional coupling shows Arnold tongue pattern in quantum synchronization.

Unidirectional coupling exhibits quantum synchronization blockade.

Quantum discord correlates with synchronization regardless of topology.

Abstract

Optically coupled optomechanical oscillators has turned out to be a versatile experimental resource for exploring optomechanical synchronizations and correlations. In this work, we investigate the phenomena of quantum synchronization and quantum correlations in two optically coupled optomechanical oscillators with two different topologies. In one case the oscillators are coupled with optical photons in a reversible manner, termed as bidirectional coupling, while in the other photons are allowed to enter to the other oscillator but not allowed to exchanged back in the opposite direction, termed as unidirectional coupling. Our results shows that irrespective of these configurations, when synchronization builds up, the two oscillators also become quantum mechanically correlated with a finite degree of Gaussian quantum discord. However, we find that depending on these topologies, both synchronization and quantum discord behave in a very distinctive manner. For instance, in bidirectionally coupled optomechanical oscillators, we find both quantum synchronization and discord exhibit a tongue like pattern which is the quantum analogue of an Arnold tongue. Whereas, in the unidirectionally coupled oscillators, we observe a novel blockade like behavior for quantum phase synchronization, also known as the quantum synchronization blockade, while quantum discord being failed to map such an anomalous behavior.