Strong tunable spin-spin interaction in a weakly coupled nitrogen vacancy spin-cavity electromechanical system

The long coherence time of a single nitrogen vacancy (NV) center spin in diamond is crucial advantage for implementing quantum information processing. However, the realization strong coupling between NV spins challenging. Here, we propose method to greatly enhance interaction two which are only weakly coupled an electromechanical cavity. Owing presence critical point linearized subsystem, and high-frequency polariton (formed by mechanical cavity modes) can be fully decoupled, but low-frequency is, however, enhanced. Thus, AC Stark shift measured. With as bus, centers achievable. This effective ensure coherent quantum-information exchange qubits spin-cavity system.