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arXiv · 2110.11537

Error-divisible two-qubit gates

David Rodriguez Perez·Paul Varosy·Ziqian Li·Tanay Roy·Eliot Kapit·David Schuster
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Abstract

We introduce a simple, widely applicable formalism for designing "error-divisible" two qubit gates: a quantum gate set where fractional rotations have proportionally reduced error compared to the full entangling gate. In current noisy intermediate-scale quantum (NISQ) algorithms, performance is largely constrained by error proliferation at high circuit depths, of which two-qubit gate error is generally the dominant contribution. Further, in many hardware implementations, arbitrary two qubit rotations must be composed from multiple two-qubit stock gates, further increasing error. This work introduces a set of criteria, and example waveforms and protocols to satisfy them, using superconducting qubits with tunable couplers for constructing continuous gate sets with significantly reduced error for small-angle rotations. If implemented at scale, NISQ algorithm performance would be significantly improved by our error-divisible gate protocols.

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David Rodriguez Perez, Paul Varosy, Ziqian Li, Tanay Roy, Eliot Kapit, David Schuster. 2021-10-22. Error-divisible two-qubit gates. https://arxiv.org/abs/2110.11537

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