Bias-preserving computation with the bit-flip code

TL;DR

This paper investigates fault-tolerant quantum computation using the bit-flip code in a biased noise environment, proposing bias-preserving gates that enhance computational accuracy in quantum simulations.

Contribution

It introduces bias-preserving implementations of key quantum gates within the bit-flip code under biased noise, improving quantum computation precision.

Findings

Bias-preserving gates reduce phase-flip errors in the bit-flip code.

Enhanced accuracy in quantum simulations and variational algorithms.

Feasibility of fault-tolerant quantum computing in biased noise channels.

Abstract

We explore the feasibility of fault-tolerant quantum computation using the bit-flip repetition code in a biased noise channel where only the bit-flip error can occur. While several logic gates can potentially produce phase-flip errors even in such a channel, we propose bias-preserving implementation of $S$, $H$, $\mathrm{CZ}$, and $R_z$ gates. We demonstrate that our scheme improves the computational precision in several tasks such as the time evolution of quantum systems and variational quantum eigensolver.