State-independent Nonadiabatic Geometric Quantum Gates

TL;DR

This paper introduces a state-independent nonadiabatic geometric quantum gate scheme that enhances robustness and fault tolerance, with a practical implementation using Rydberg atoms for multiqubit control-phase gates.

Contribution

It presents a fully geometric, state-independent nonadiabatic quantum gate scheme with improved robustness and a detailed Rydberg atom implementation for fault-tolerant quantum computing.

Findings

Significantly stronger gate robustness than previous schemes.

Achieves fault-tolerance threshold in multiqubit gates.

Provides a feasible physical implementation with Rydberg atoms.

Abstract

Quantum computation has demonstrated advantages over classical computation for special hard problems, where a set of universal quantum gates is essential. Geometric phases, which have built-in resilience to local noise, have been used to construct quantum gates with excellent performance. However, this advantage has been smeared in previous schemes. Here, we propose a state-independent nonadiabatic geometric quantum-gate scheme that is able to realize a more fully geometric gate than previous approaches, allowing for the cancelation of dynamical phases accumulated by an arbitrary state. Numerical simulations demonstrate that our scheme has significantly stronger gate robustness than the previous geometric and dynamical ones. Meanwhile, we give a detailed physical implementation of our scheme with the Rydberg atom system based on the Rydberg blockade effect, specifically for multiqubit control-phase gates, which exceeds the fault-tolerance threshold of multiqubit quantum gates within the considered error range. Therefore, our scheme provides a promising way for fault-tolerant quantum computation in atomic systems.