Suppression of mid-circuit measurement crosstalk errors with micromotion

TL;DR

This paper introduces a micromotion-based technique to significantly reduce measurement crosstalk errors in trapped ion quantum systems, enabling more precise mid-circuit operations.

Contribution

It presents a novel micromotion method to suppress crosstalk errors during mid-circuit measurements in trapped ion quantum computers.

Findings

Over an order of magnitude reduction in crosstalk errors.

Effective measurement and reset with low crosstalk demonstrated on Honeywell H0 system.

New benchmarking method based on randomized benchmarking.

Abstract

Mid-circuit measurement and reset are crucial primitives in quantum computation, but such operations require strong interactions with selected qubits while maintaining isolation of neighboring qubits, which is a significant challenge in many systems. For trapped ion systems, measurement is performed with laser-induced fluorescence. Stray light from the detection beam and fluorescence from the measured ions can be significant sources of decoherence for unmeasured qubits. We present a technique using ion micromotion to reduce these sources of decoherence by over an order of magnitude. We benchmark the performance with a new method, based on randomized benchmarking, to estimate the magnitude of crosstalk errors on nearby qubits. Using the Honeywell System Model H0, we demonstrate measurement and reset on select qubits with low crosstalk errors on neighboring qubits.