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This content will become publicly available on October 12, 2024

Title: High-fidelity gates and mid-circuit erasure conversion in an atomic qubit
The development of scalable, high-fidelity qubits is a key challenge in quantum information science. Neutral atom qubits have progressed rapidly in recent years, demonstrating programmable processors1,2 and quantum simulators with scaling to hundreds of atoms3,4. Exploring new atomic species, such as alkaline earth atoms5,6,7, or combining multiple species8 can provide new paths to improving coherence, control and scalability. For example, for eventual application in quantum error correction, it is advantageous to realize qubits with structured error models, such as biased Pauli errors9 or conversion of errors into detectable erasures10. Here we demonstrate a new neutral atom qubit using the nuclear spin of a long-lived metastable state in 171Yb. The long coherence time and fast excitation to the Rydberg state allow one- and two-qubit gates with fidelities of 0.9990(1) and 0.980(1), respectively. Importantly, a large fraction of all gate errors result in decays out of the qubit subspace to the ground state. By performing fast, mid-circuit detection of these errors, we convert them into erasure errors; during detection, the induced error probability on qubits remaining in the computational space is less than 10−5. This work establishes metastable 171Yb as a promising platform for realizing fault-tolerant quantum computing.  more » « less
Award ID(s):
2120757
NSF-PAR ID:
10505949
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Publisher / Repository:
Springer Nature
Date Published:
Journal Name:
Nature
Volume:
622
Issue:
7982
ISSN:
0028-0836
Page Range / eLocation ID:
279 to 284
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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