Industry-compatible silicon spin-qubit unit cells exceeding 99% fidelity
- Paul Steinacker
- Nard Dumoulin Stuyck
- Wee Han Lim
- Tuomo Tanttu
- MengKe Feng
- Santiago Serrano
- Andreas Nickl
- Marco Candido
- Jesus D. Cifuentes
- Ensar Vahapoglu
- Samuel K. Bartee
- Fay E. Hudson
- Kok Wai Chan
- Stefan Kubicek
- Julien Jussot
- Yann Canvel
- Sofie Beyne
- Yosuke Shimura
- Roger Loo
- Clement Godfrin
- Bart Raes
- Sylvain Baudot
- Danny Wan
- Arne Laucht
- Chih Hwan Yang
- Andre Saraiva
- Christopher C. Escott
- Kristiaan De Greve
- Andrew S. Dzurak
2025-09-24
Among the many types of qubit presently being investigated for a future quantum computer, silicon spin qubits with millions of qubits on a single chip are uniquely positioned to enable quantum computing. However, it has not been clear whether the outstanding high-fidelity operations and long coherence times shown by silicon spin qubits fabricated in academic settings 1–8 can be reliably reproduced when the qubits are manufactured in a semiconductor foundry 9–11 . Here we show precise qubit operation of silicon two-qubit devices made with standard semiconductor tooling in a 300-mm foundry environment. Of the key metrics, single- and two-qubit control fidelities exceed 99% for all four devices, and the state preparation and measurement fidelities reach up to 99.9%, as evidenced by gate set tomography. We report spin lifetime and coherence up to T 1 = 9.5 s, $${T}_{2}^{* }=40.6\,{\rm{\mu }}{\rm{s}}$$ T 2 * = 40.6 μ s and $${T}_{2}^{{\rm{Hahn}}}=1.9\,{\rm{ms}}$$ T 2 Hahn = 1.9 ms . We determine that residual nuclear spin-carrying isotopes contribute substantially to operational errors, identifying further isotopic purification as a clear pathway to even higher performance.