Deterministic and Robust Entanglement of Nitrogen Vacancy Centers using Low-Q Photonic Crystal Cavities

TL;DR

This paper proposes a method to generate deterministic and robust entanglement between nitrogen vacancy centers using low-Q photonic crystal cavities, demonstrating feasibility with current technology and insensitivity to spectral variations.

Contribution

The study introduces a new scheme for entangling NV centers via photonic crystal cavities that is robust and effective with moderate Q-factors, advancing practical quantum network development.

Findings

Achieves concurrence >0.6 with Q=10^4 within 150 ns

Achieves concurrence >0.8 with Q=10^5

Scheme is insensitive to spectral diffusion and frequency differences

Abstract

We propose an experiment to generate deterministic entanglement between separate nitrogen vacancy (NV) centers mediated by the mode of a photonic crystal cavity. Using numerical simulations the applicability and robustness of the entanglement operation to parameter regimes achievable with present technology is investigated. We find that even with moderate cavity Q-factors of $10^{4}$ a concurrence of $c>0.6$ can be achieved within a time of $t_{max}\approx150$~ns, while Q-factors of $10^{5}$ promise $c>0.8$. Most importantly, the investigated scheme is relative insensitive to spectral diffusion and differences between the optical transitions frequencies of the used NV centers.