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arXiv · 2401.06705

Fidelity of photon-mediated entanglement between remote nuclear-spin multi-qubit registers

W. -R. Hannes·Regina Finsterhoelzl·Guido Burkard
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Abstract

The electron spin of a nitrogen-vacancy center in diamond lends itself to the control of proximal $^{13}$C nuclear spins via dynamical decoupling methods, possibly combined with radio-frequency driving. Long-lived single-qubit states and high-fidelity electron-nuclear gates required for the realization of a multiqubit register have already been demonstrated. Towards the goal of a scalable architecture, linking multiple such registers in a photonic network represents an important step. Multiple pairs of remotely entangled qubits can enable advanced algorithms or error correction protocols. We investigate how a photonic architecture can be extended from the intrinsic nitrogen spin to multiple $^{13}$C spins per node. Applying decoherence-protected gates sequentially, we simulate the fidelity of creating multiple pairs of remotely entangled qubits. Even though the currently achieved degree of control of $^{13}$C spins might not be sufficient for large-scale devices, the two schemes are compatible in principle. One requirement is the correction of unconditional phases acquired by unaddressed nuclear spins during a decoupling sequence.

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W. -R. Hannes, Regina Finsterhoelzl, Guido Burkard. 2024-01-12. Fidelity of photon-mediated entanglement between remote nuclear-spin multi-qubit registers. https://doi.org/10.1103/physreva.110.052436

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