Error mitigation via stabilizer measurement emulation

TL;DR

This paper introduces Quantum Measurement Emulation (QME), a novel error mitigation method that emulates stabilizer measurements through stochastic gates, effectively suppressing certain coherent errors without requiring measurements or feedback.

Contribution

The paper presents QME, a new technique that emulates stabilizer measurements to mitigate errors, especially coherent errors, without the need for costly measurement and feedback.

Findings

QME effectively suppresses first-order coherent errors.

QME is well-suited for discrete coherent errors difficult for dynamical decoupling.

QME does not require measurements or feedback, reducing resource overhead.

Abstract

Dynamical decoupling (DD) is a widely-used quantum control technique that takes advantage of temporal symmetries in order to partially suppress quantum errors without the need resource-intensive error detection and correction protocols. This and other open-loop error mitigation techniques are critical for quantum information processing in the era of Noisy Intermediate-Scale Quantum technology. However, despite its utility, dynamical decoupling does not address errors which occur at unstructured times during a circuit, including certain commonly-encountered noise mechanisms such as cross-talk and imperfectly calibrated control pulses. Here, we introduce and demonstrate an alternative technique - `quantum measurement emulation' (QME) - that effectively emulates the measurement of stabilizer operators via stochastic gate application, leading to a first-order insensitivity to coherent errors. The QME protocol enables error suppression based on the stabilizer code formalism without the need for costly measurements and feedback, and it is particularly well-suited to discrete coherent errors that are challenging for DD to address.