Dissipative preparation of entangled states between two spatially separated nitrogen-vacancy centers

We present an efficient scheme for the generation of entangled states of two spatially separated nitrogen-vacancy (NV) centers with two whispering-gallery-mode (WGM) microresonators, which are coupled either by an optical fiber-taper waveguide or by the evanescent fields of the WGM. We show that the steady state of the two NV centers can be steered into a singletlike state through a dissipative quantum dynamical process, where the cavity decay plays a positive role and can help drive the system to the target state. The protocol may open up promising perspectives for quantum communication and computation with this solid-state cavity quantum electrodynamic system.