Long-range quantum correlations based on quantum coherence in a hybrid system

Abstract We propose a scheme to realize long-range quantum correlations of two separated ensembles of nitrogen-vacancy (NV) centers via asymmetric driving. Either of the ensembles of NV centers is dynamically driven by a strong applied microwave field, which causes the coupled energy levels to split into dressed states. A quantum electromechanical system (QEMS), as a quantum data bus, connects the two ensembles of NV centers. When a weak microwave field in QEMS couples the same energy level transitions of the two ensembles of NV centers, the beam-splitter-like interactions are realized. The collective mode of the mechanical resonators in the QEMS is near-resonant with the dressed energy level establishing the parametric down-conversion-like interaction. The Kerr nonlinearity produced by the parametric down-conversion-like interaction can be transferred by the beam-splitter-like interactions. We demonstrate the photon-phonon one-way Einstein–Podolsky–Rosen steering, and spin squeezing. Our scheme can thereafter support a potential application of the generalized storage of quantum information.