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.
@article{arxiv.2110.11537,
title = {Error-divisible two-qubit gates},
author = {David Rodriguez Perez and Paul Varosy and Ziqian Li and Tanay Roy and Eliot Kapit and David Schuster},
journal= {arXiv preprint arXiv:2110.11537},
year = {2021}
}
Comments
5 pages main text, 11 pages total, 5 figures main text, 10 figures total, 3 tables in appendix