Towards Quantum Gates with Wide Operating Margins

TL;DR

This paper proposes a novel quantum gate scheme using nonlinearities and subsystem codes to achieve wide operating margins, enhancing robustness against noise and imperfections in quantum hardware.

Contribution

It introduces a composite qubit and gate scheme leveraging transistor-like nonlinearities and adiabatic deformation of subsystem codes for improved quantum gate robustness.

Findings

Simulation of a superconducting circuit demonstrating core elements

The scheme suppresses ambient noise and control imperfections

Discussion of experimental implementation challenges

Abstract

Scaling up quantum computing hardware is hindered by the narrow operating margins of current quantum components. Here, we introduce a composite qubit and gate scheme that achieves wide margins by use of transistor-like nonlinearities to suppress the effects of both ambient noise and control signal imperfections. This is accomplished by adiabatic deformation of subsystem codes based on anti-commuting two-body interactions. We focus on a resource-effcient variation that exploits biased noise and preserves bias under gate operation. As a proof of concept, we present simulations of a superconducting circuit that demonstrates core elements of the approach and discuss the challenges of experimental implementation.