Enhanced electromechanical entanglement in a coupled optoelectromechanical system

Quantum entanglement, as a central concept in quantum theory, plays a crucial role in understanding the fundamentals of quantum mechanics and is widely studied in advanced practical technological applications. We study the behavior of bipartite and tripartite entanglement in a hybrid optoelectromechanical system consisting of a pair of coupled cavities, a large mass membrane, and a low-frequency $LC$ resonator. Within the experimentally achievable parameters, we observe a significant enhancement of the electromechanical entanglement, which directly originates from the electromechanical coupling. We also show that entanglement between subsystems can be manipulated by tuning the cavity-cavity coupling rate. Furthermore, we significantly enhance the robustness of electromechanical entanglement against thermal noise. The enhancement of electromechanical entanglement in this system will facilitate the investigation of quantum theory applications on more macroscopic scales, such as medical imaging, quantum communication, and astronomical signal detection.