Digital zero noise extrapolation for quantum error mitigation

TL;DR

This paper enhances zero-noise extrapolation (ZNE) for quantum error mitigation by introducing digital noise scaling methods and an adaptive extrapolation protocol, achieving significant error reductions and enabling practical use on larger quantum systems.

Contribution

It proposes digital noise scaling frameworks and an adaptive extrapolation method, improving ZNE's effectiveness and practicality for quantum error mitigation.

Findings

Error reductions of 18X to 24X demonstrated

Effective at larger qubit numbers than previous tests

Provides a self-contained guide for quantum programmers

Abstract

Zero-noise extrapolation (ZNE) is an increasingly popular technique for mitigating errors in noisy quantum computations without using additional quantum resources. We review the fundamentals of ZNE and propose several improvements to noise scaling and extrapolation, the two key components in the technique. We introduce unitary folding and parameterized noise scaling. These are digital noise scaling frameworks, i.e. one can apply them using only gate-level access common to most quantum instruction sets. We also study different extrapolation methods, including a new adaptive protocol that uses a statistical inference framework. Benchmarks of our techniques show error reductions of 18X to 24X over non-mitigated circuits and demonstrate ZNE effectiveness at larger qubit numbers than have been tested previously. In addition to presenting new results, this work is a self-contained introduction to the practical use of ZNE by quantum programmers.