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arXiv · 2209.05631

Coherent control of a nuclear spin via interactions with a rare-earth ion in the solid-state

Mehmet T. Uysal·Mouktik Raha·Songtao Chen·Christopher M. Phenicie·Salim Ourari·Mengen Wang·Chris G. Van de Walle·Viatcheslav V. Dobrovitski·Jeff D. Thompson
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Abstract

Individually addressed Er$^{3+}$ ions in solid-state hosts are promising resources for quantum repeaters, because of their direct emission in the telecom band and compatibility with silicon photonic devices. While the Er$^{3+}$ electron spin provides a spin-photon interface, ancilla nuclear spins could enable multi-qubit registers with longer storage times. In this work, we demonstrate coherent coupling between the electron spin of a single Er$^{3+}$ ion and a single $I=1/2$ nuclear spin in the solid-state host crystal, which is a fortuitously located proton ($^1$H). We control the nuclear spin using dynamical decoupling sequences applied to the electron spin, implementing one- and two-qubit gate operations. Crucially, the nuclear spin coherence time exceeds the electron coherence time by several orders of magnitude, because of its smaller magnetic moment. These results provide a path towards combining long-lived nuclear spin quantum registers with telecom-wavelength emitters for long-distance quantum repeaters.

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Mehmet T. Uysal, Mouktik Raha, Songtao Chen, Christopher M. Phenicie, Salim Ourari, Mengen Wang, Chris G. Van de Walle, Viatcheslav V. Dobrovitski, Jeff D. Thompson. 2022-09-12. Coherent control of a nuclear spin via interactions with a rare-earth ion in the solid-state. https://doi.org/10.1103/prxquantum.4.010323

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