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arXiv · 2408.15329

Site-selective cavity readout and classical error correction of a 5-bit atomic register

Beili Hu·Josiah Sinclair·Edita Bytyqi·Michelle Chong·Alyssa Rudelis·Joshua Ramette·Zachary Vendeiro·Vladan Vuletić
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Abstract

Optical cavities can provide fast and non-destructive readout of individual atomic qubits; however, scaling up to many qubits remains a challenge. Using locally addressed excited-state Stark shifts to tune atoms out of resonance, we realize site-selective hyperfine-state cavity readout across a 10-site array. The state discrimination fidelity is 0.994(1) for one atom and 0.989(2) averaged over the entire array at a survival probability of 0.975(1). To further speed up array readout, we demonstrate adaptive search strategies utilizing global/subset checks. Finally, we demonstrate repeated rounds of classical error correction, showing exponential suppression of logical error and extending logical memory fivefold beyond the single-bit idling lifetime.

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Beili Hu, Josiah Sinclair, Edita Bytyqi, Michelle Chong, Alyssa Rudelis, Joshua Ramette, Zachary Vendeiro, Vladan Vuletić. 2024-08-27. Site-selective cavity readout and classical error correction of a 5-bit atomic register. https://arxiv.org/abs/2408.15329

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