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arXiv · 2108.04790

Assembly and coherent control of a register of nuclear spin qubits

Katrina Barnes·Peter Battaglino·Benjamin J. Bloom·Kayleigh Cassella·Robin Coxe·Nicole Crisosto·Jonathan P. King·Stanimir S. Kondov·Krish Kotru·Stuart C. Larsen·Joseph Lauigan·Brian J. Lester·Mickey McDonald·Eli Megidish·Sandeep Narayanaswami·Ciro Nishiguchi·Remy Notermans·Lucas S. Peng·Albert Ryou·Tsung-Yao Wu·Michael Yarwood
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Abstract

We introduce an optical tweezer platform for assembling and individually manipulating a two-dimensional register of nuclear spin qubits. Each nuclear spin qubit is encoded in the ground $^{1}S_{0}$ manifold of $^{87}$Sr and is individually manipulated by site-selective addressing beams. We observe that spin relaxation is negligible after 5 seconds, indicating that $T_1\gg5$ s. Furthermore, utilizing simultaneous manipulation of subsets of qubits, we demonstrate significant phase coherence over the entire register, estimating $T_2^\star = \left(21\pm7\right)$ s and measuring $T_2^\text{echo}=\left(42\pm6\right)$ s.

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Katrina Barnes, Peter Battaglino, Benjamin J. Bloom, Kayleigh Cassella, Robin Coxe, Nicole Crisosto, Jonathan P. King, Stanimir S. Kondov, Krish Kotru, Stuart C. Larsen, Joseph Lauigan, Brian J. Lester, Mickey McDonald, Eli Megidish, Sandeep Narayanaswami, Ciro Nishiguchi, Remy Notermans, Lucas S. Peng, Albert Ryou, Tsung-Yao Wu, Michael Yarwood. 2021-08-10. Assembly and coherent control of a register of nuclear spin qubits. https://doi.org/10.1038/s41467-022-29977-z

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