Arbitrary control of entanglement between two nitrogen-vacancy-center ensembles coupling to a superconducting-circuit qubit

We propose an effective scheme for realizing a Jaynes-Cummings model with the collective nitrogen-vacancycenter ensemble (NVE) bosonic modes in a hybrid system. Specifically, the controllable transmon qubit can alternatively interact with one of the two NVEs, which results in the production of N-particle entangled states. Arbitrary N-particle entangled states, NOON states, N-dimensional entangled states, and entangled coherent states are demonstrated. Realistic imperfections and decoherence effects are analyzed via numerical simulation. Since no cavity photons or excited levels of the NV center are populated during the whole process, our scheme is insensitive to cavity decay and the spin dephasing effect of the NVE. The idea provides a scalable way to realize NVE-circuit cavity quantum information processing with current technology.