Continuous-variable multipartite vibrational entanglement

A compact scheme for the preparation of macroscopic multipartite entanglement is proposed and analyzed. In this scheme, the vibrational modes of a mechanical resonator constitute continuous-variable (CV) subsystems that entangle with each other as a result of their interaction with a two-level system (TLS). By properly driving the TLS, we show that a selected set of modes can be activated and prepared in a multipartite entangled state. We first study the entanglement properties of a three-mode system by evaluating the genuine multipartite entanglement, and we investigate its usefulness as a quantum resource by computing the quantum Fisher information. Moreover, the robustness of the state against the qubit and thermal noises is studied, proving a long-lived entanglement. To examine the scalability and structural properties of the scheme, we derive an effective model for the multimode system through elimination of the TLS dynamics. This work provides a step toward a compact and versatile device for creating a multipartite noise-resilient entangled state in vibrational modes as a resource for CV quantum metrology, quantum communication, and quantum computation.