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arXiv · 1911.12240

Path-Independent Quantum Gates with Noisy Ancilla

Wen-Long Ma·Mengzhen Zhang·Yat Wong·Kyungjoo Noh·Serge Rosenblum·Philip Reinhold·Robert J. Schoelkopf·Liang Jiang
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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.

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Wen-Long Ma, Mengzhen Zhang, Yat Wong, Kyungjoo Noh, Serge Rosenblum, Philip Reinhold, Robert J. Schoelkopf, Liang Jiang. 2019-11-27. Path-Independent Quantum Gates with Noisy Ancilla. https://doi.org/10.1103/physrevlett.125.110503

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