High-Fidelity Hybrid Quantum Gates between a Flying Photon and Diamond Nitrogen-Vacancy Centers Assisted by Low-Q Single-Sided Cavities

摘要

High-fidelity universal quantum gates are crucial in quantum computing. Three high-fidelity universal quantum gates, namely the hybrid controlled NOT gate, the hybrid Toffoli gate, and the hybrid Fredkin gate, on a flying photon qubit and diamond nitrogen-vacancy (NV) centers, assisted by low-Q single-sided cavities, are presented. Errors due to the imperfection of the practical input-output process are detected to improve the fidelity of these quantum gates, which therefore relaxes the requirement on their implementation, since strong coupling is no longer mandatory. In addition, quantum gates have the advantage that they can work faithfully even when the resonant condition among the NV center, the photon, and the cavity is not strictly satisfied, or the NV centers are not identical. The performance and success probability of these quantum gates are analyzed, finding that these schemes are feasible with current technology.