Preparing multiparticle entangled states of nitrogen-vacancy centers via adiabatic ground-state transitions

We propose an efficient method to generate multiparticle entangled states of nitrogen-vacancy (NV) centers in a spin-mechanical system, where the spins interact through a collective coupling of the Lipkin-Meshkov-Glick (LMG) type. We show that through adiabatic transitions in the ground state of the LMG Hamiltonian, the Greenberger-Horne-Zeilinger (GHZ)-type or the W-type entangled states of the NV spins can be generated with this hybrid system from an initial product state. Because of adiabaticity, this scheme is robust against practical noise and experimental imperfection, and may be useful for quantum information processing.