Optimal Qubit Control Using Single-Flux Quantum Pulses

TL;DR

This paper demonstrates that optimized single-flux quantum pulse sequences, designed via genetic algorithms, can achieve high-fidelity single-qubit rotations in superconducting qubits, even with timing jitter, advancing on-chip quantum control.

Contribution

It introduces an optimization method using genetic algorithms for single-flux quantum pulses to improve qubit control fidelity, accounting for timing jitter.

Findings

Reduced gate error by 100x compared to uniform pulses

Genetic algorithms effectively optimize pulse sequences

Robustness of control sequences against timing jitter

Abstract

Single flux quantum pulses are a natural candidate for on-chip control of superconducting qubits. We show that they can drive high-fidelity single-qubit rotations---even in leaky transmon qubits---if the pulse sequence is suitably optimized. We achieve this objective by showing that, for these restricted all-digital pulses, genetic algorithms can be made to converge to arbitrarily low error, verified up to a reduction in gate error by 2 orders of magnitude compared to an evenly spaced pulse train. Timing jitter of the pulses is taken into account, exploring the robustness of our optimized sequence. This approach takes us one step further towards on-chip qubit controls.