Secure quantum communication via Einstein-Podolsky-Rosen steering between remotely coupled optomechanical systems
Phys. Rev. A 113, 013521 – Published 13 January, 2026
DOI: https://doi.org/10.1103/33k5-cc9d
Abstract
Quantum communication offers a unique framework for unconditional security, where secret key distribution can be used to establish trusted links across insecure networks. We propose a semi-device-independent scheme with two spatially separated mechanical oscillators, indirectly coupled via a lossy optical channel within a cascaded optomechanical setup. This architecture utilizes linearized optomechanical regimes to generate secret key rates through the conditional measurements of the mechanical modes' conjugate variables. It also exhibits asymmetric quantum steering features and position-momentum squeezing under realistic, noise-attenuated transmission conditions. We analyze the achievable key rate in the presence of optical losses and excess noise introduced by untrusted parties, and thermal noise, demonstrating the scheme's potential for secure long-distance communication. This proof-of-principle theoretical approach offers a promising foundation for extending similar schemes in entangled hybrid quantum networks.
