Universal flux-based control of a $\pi$-SQUID

• URL: http://arxiv.org/abs/2312.04321v2
• Date: Mon, 26 Feb 2024 06:54:18 GMT
• Title: Universal flux-based control of a $\pi$-SQUID
• Authors: J. Wilson Staples, Thomas B. Smith, Andrew C. Doherty
• Abstract summary: We describe a protocol for the universal control of non-ideal $pi$-periodic superconducting qubits. Our proposal relies on a $pi$-SQUID: a superconducting loop formed by two $pi$-periodic circuit elements.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: We describe a protocol for the universal control of non-ideal $\pi$-periodic superconducting qubits. Our proposal relies on a $\pi$-SQUID: a superconducting loop formed by two $\pi$-periodic circuit elements, with an external magnetic flux threading the circuit. The system exhibits an extensive sweet spot around half-flux where residual $2\pi$-periodic Cooper pair tunneling is highly suppressed. We demonstrate that universal single-qubit operations can be realised by tuning the flux adiabatically and diabatically within this broad sweet spot. We also assess how residual $2\pi$-periodicity in $\pi$-SQUIDs impacts holonomic phase gates.

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