Learning time-dependent noise to reduce logical errors: Real time error rate estimation in quantum error correction

TL;DR

This paper introduces a real-time error rate estimation protocol for quantum error correction that leverages Gaussian processes, enabling adaptive error mitigation without interrupting ongoing quantum computations.

Contribution

It presents a novel protocol for real-time error rate monitoring in quantum error correction that does not require code modifications or circuit changes.

Findings

Error correction failure probability can be significantly reduced.

The protocol is compatible with advanced quantum error correction techniques like surface codes.

Using estimated error rates improves the reliability of quantum information processing.

Abstract

Quantum error correction is important to quantum information processing, which allows us to reliably process information encoded in quantum error correction codes. Efficient quantum error correction benefits from the knowledge of error rates. We propose a protocol for monitoring error rates in real time without interrupting the quantum error correction. Any adaptation of the quantum error correction code or its implementation circuit is not required. The protocol can be directly applied to the most advanced quantum error correction techniques, e.g. surface code. A Gaussian processes algorithm is used to estimate and predict error rates based on error correction data in the past. We find that using these estimated error rates, the probability of error correction failures can be significantly reduced by a factor increasing with the code distance.