Suppressing crosstalk for Rydberg quantum gates

TL;DR

This paper introduces a spin-echo-inspired protocol to significantly reduce crosstalk in Rydberg quantum gates, enhancing gate fidelity for neutral atom quantum computing.

Contribution

It proposes a novel gate protocol that suppresses crosstalk and phase errors, improving fidelity in Rydberg-based quantum gates with local addressing.

Findings

Fidelity improved by two orders of magnitude

Effective suppression of crosstalk in neutral atom systems

Broad applicability across experimental parameters

Abstract

We present a method to suppress crosstalk from implementing controlled-Z gates via local addressing in neutral atom quantum computers. In these systems, a fraction of the laser light that is applied locally to implement gates typically leaks to other atoms. We analyze the resulting crosstalk in a setup of two gate atoms and one neighboring third atom. We then perturbatively derive a spin-echo-inspired gate protocol that suppresses the leading order of the amplitude error, which dominates the crosstalk. Numerical simulations demonstrate that our gate protocol improves the fidelity by two orders of magnitude across a broad range of experimentally relevant parameters. To further reduce the infidelity, we develop a circuit to cancel remaining phase errors. Our results pave the way for using local addressing for high-fidelity quantum gates on Rydberg-based quantum computers.