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arXiv · 2505.09292

Robust transfer of a quantum state from an absorbed photon into a diamond spin

Daisuke Ito·Yuhei Sekiguchi·Raustin Reyes·Taichi Fujiwara·Toshiharu Makino·Hiromitsu Kato·Hideo Kosaka
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Abstract

Conversion of a quantum state from a flying qubit to a memory qubit is crucial for distributed quantum computing. However, this requires precise spatiotemporal or frequency/phase alignment. Here, we experimentally demonstrate quantum teleportation-based state transfer from a photon into a spin in a nitrogen-vacancy center in diamond robust against both spectral and temporal errors. The achieved fidelity exceeds 0.94 within a frequency error of 100 MHz and 0.93 within an arrival-time error of 100 ns. This achievement enables extraordinarily robust entanglement generation between remote quantum memories compared with the conventional photon-interference-based approaches and paves the way for stable quantum networks.

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Daisuke Ito, Yuhei Sekiguchi, Raustin Reyes, Taichi Fujiwara, Toshiharu Makino, Hiromitsu Kato, Hideo Kosaka. 2025-05-14. Robust transfer of a quantum state from an absorbed photon into a diamond spin. https://arxiv.org/abs/2505.09292

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