Records

Tantalum-on-silicon 2D transmon lifetime

Tantalum-on-silicon 2D transmon lifetime in the Records: every value read on the maker's own pages, with its day.

Measure: Coherence time — arxiv.org, read 20 October 2026
Value: 1.68 ms — arxiv.org, read 20 October 2026
Reported: 19 March 2025 — arxiv.org, read 20 October 2026
Method: Not confirmed: two readings disagree: Here we show that replacing the substrate with high-resistivity silicon (Si) dramatically decreases the bulk substrate loss, enabling 2D transmons with time-averaged quality factors (Q) exceeding 1.5 x 10^7, reaching a maximum Q of 2.5 x 10^7, corresponding to a lifetime (T_1) of up to 1.68 ms. and Tantalum-on-high-resistivity silicon 2D transmons with improved junction deposition
Paper or release: https://arxiv.org/abs/2503.14798 — arxiv.org, read 20 October 2026
Peer reviewed: Yes — www.nature.com, read 20 October 2026

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