Segmented Composite Design of Robust Single-Qubit Quantum Gates

TL;DR

This paper introduces a composite segmented design method for creating robust single-qubit quantum gates that effectively mitigate errors by considering the full noise distribution, demonstrated in photonic systems.

Contribution

It presents a novel error mitigation scheme using composite segmented design that accounts for complete noise distributions, with two optimization approaches for robust single-qubit gates.

Findings

Reduces error by an order of magnitude in photonic systems

Compatible perturbative and non-perturbative approaches for small errors

Significantly decreases overhead of error correction codes

Abstract

Error mitigation schemes and error-correcting codes have been the center of much effort in quantum information processing research over the last few decades. While most of the successful proposed schemes for error mitigation are perturbative in the noise and assume deterministic systematic errors, studies of the problem considering the full noise and errors distribution are still scarce. In this work, we introduce an error mitigation scheme for robust single-qubit unitary gates based on composite segmented design, which accounts for the full distribution of the physical noise and errors in the system. We provide two optimization approaches to construct these robust segmented gates: perturbative and non-perturbative, that addresses all orders of errors. We demonstrate our scheme in the photonics realm for the dual-rail directional couplers realization. We show that the 3-segmented composite design for the fundamental single-qubits unitary operations reduces the error by an order of magnitude for a realistic distribution of errors, and that the two approaches are compatible for small errors. This is shown to significantly reduce the overhead of modern error correction codes. Our methods are rather general and can be applied to other realizations of quantum information processing units.