Limits RegistryPUBLIC RECORD
Limits RegistryKihwan Kim's group at Tsinghua University reported a coherence time of about 37,700 seconds (roughly 10.5 hours) for a qubit encoded in a decoherence-free subspace of two ytterbium-171 ions, sympathetically cooled by barium ions, in a March 2026 preprint. The same group had previously reported about 5,500 seconds for a single-ion qubit in Nature Communications in 2021.
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Kihwan Kim's group at Tsinghua University reported a coherence time of about 37,700 seconds (roughly 10.5 hours) for a qubit encoded in a decoherence-free subspace of two ytterbium-171 ions, sympathetically cooled by barium ions, in a March 2026 preprint. The same group had previously reported about 5,500 seconds for a single-ion qubit in Nature Communications in 2021.
The longest measured coherence time of a qubit encoded in trapped atomic ions.
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Permanent ID limitsregistry.com/limits/LR-LONGEST-TRAPPED-ION-QUBIT-COHERENCE
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Limits Registry. LR-LONGEST-TRAPPED-ION-QUBIT-COHERENCE. Longest coherence time of a trapped-ion qubit. 2026.