Thermal-noise-resistant entanglement and steering via dark-mode engineering in multimode optomechanical system

Abstract We propose a scheme for generating thermal-noise-resistant entanglement and Einstein-Podolsky-Rosen (EPR) steering in a multimode optomechanical system by breaking the dark mode effect. Here, the dark mode is broken by coupling an auxiliary cavity to one of the mechanical modes. Under this condition, strong entanglement and one-way EPR steering between two mechanical modes are achieved through the cooperative interaction of an optical parametric amplifier and a squeezed vacuum field. Furthermore, our results demonstrate that breaking the dark mode effect significantly enhances the robustness of steady-state entanglement and asymmetric EPR steering against thermal noise. We further provide a physical interpretation of the generation and suppression of the dark mode effect. This work offers a promising approach for creating macroscopic quantum resources that are resistant to noise, with potential applications in quantum information processing.