We explore the entanglement generation and the corresponding dynamics between two separate nitrogen-vacancy (NV) centers in diamond nanocrystal coupled to a photonic molecule consisting of a pair of coupled photonic crystal (PC) cavities. By calculating the entanglement concurrence with readily available experimental parameters, it is found that the entanglement degree strongly depends on the cavity-cavity hopping strength and the NV-center-cavity detuning. High concurrence peak and long-lived entanglement plateau can be achieved by properly adjusting practical system parameters. Meanwhile, we also discuss the influence of the coupling strength between the NV centers and the cavity modes on the behavior of the concurrence. Such a PC-NV system can be employed for quantum entanglement generation and represents a building block for an integrated nanophotonic network in a solid-state cavity quantum electrodynamics platform. In addition, the present theory can also be applied to other similar systems, such as two single quantum emitters positioned close to a microtoroidal resonator with the whispering-gallery-mode fields propagating inside the resonator.
We investigate dynamics of a laser-driven and dissipative system consisting of two nitrogen-vacancy (N-
V) centers embedded in two spatially separated single-mode nanocavities in a planar photonic crystal (PC). Spontaneous emission from the excited states of the N-
V centers can be effectively suppressed by virtue of the Raman transition in the dispersive regime. The system displays a series of damped oscillations under various experimental situations, where we solve the time-dependent Schr\"odinger equation analytically for arbitrary values of the hopping and PC--N-
V coupling strengths. In particular, our results indicate that some special values should be taken for the hopping strength if we hope to have high-fidelity quantum state transfer between the two distant N-
V centers. We have also analyzed the relevant entanglement dynamics in the presence of decoherence. The experimental feasibility and challenge are justified using currently available technology.
Abstract We theoretically investigate an efficient scheme for quantum state transfer (QST) between two nitrogen-vacancy (N-V) centers coupled to the whispering gallery modes (WGM) of a micro-resonator. We analyze the impact of mode coupling and the distance between two N-V centers on the dynamics of state transfer. Specifically, we explore QST under three coupling regimes:comparable coupling (J ≃ g), strong mode coupling J ≫ g, and weak mode coupling J ≪ g, also incorporating system decay factors (WGM decay Γ and N-V dephasing γ) at different interparticle distances. Our study shows that by adjusting the system control parameters, quantum information can be transferred between N-V centers with high efficiency. Additionally, the fidelity of QST reaches approximately 99% in all cases, with an oscillatory pattern, reflecting the intricate interplay between NV-resonator and mode coupling strengths. These findings underscore the importance of interparticle distance and mode coupling in the realization of solid-state qubit-based quantum information processing devices.