Path-Independent Quantum Gates with Noisy Ancilla

TL;DR

This paper introduces a framework combining quantum control and error correction to create robust quantum gates that are resistant to noise in ancilla systems, enhancing quantum computing reliability.

Contribution

It proposes a novel path independence criterion for fault-tolerant quantum gates that mitigates ancilla-induced decoherence in quantum systems.

Findings

Path-independent gates demonstrate robustness against ancilla noise.

The framework is applicable to superconducting circuits with efficient hardware design.

Enhanced fault tolerance in quantum gate operations.

Abstract

Ancilla systems are often indispensable to universal control of a nearly isolated quantum system. However, ancilla systems are typically more vulnerable to environmental noise, which limits the performance of such ancilla-assisted quantum control. To address this challenge of ancilla-induced decoherence, we propose a general framework that integrates quantum control and quantum error correction, so that we can achieve robust quantum gates resilient to ancilla noise. We introduce the path independence criterion for fault-tolerant quantum gates against ancilla errors. As an example, a path-independent gate is provided for superconducting circuits with a hardware-efficient design.