arXiv:2210.14521 · Physical Review Applied

Geometric correspondence of noisy quantum dynamics and universal robust quantum gates

Yong-Ju Hai, Yao Song, Junning Li, Junkai Zeng, Xiu–Hao Deng

Published May 1, 2025• 8 citations

Abstract

Quantum information processing faces a significant hurdle: noise. Different noise sources induce varying errors in quantum operations depending on the underlying dynamics. To gain a deeper understanding of these error mechanisms, we introduce the concept of quantum error evolution diagrams (QEEDs). QEEDs establish a dual correspondence between driven noisy quantum dynamics and geometric space curves, providing quantitative geometric metrics to assess the severity of the noises. This framework enables the design of universal robust quantum gates that correct errors induced by generic noise. Additionally, we present a protocol for constructing a universal set of single- and two-qubit robust quantum gates with simple and smooth control pulses of arbitrary length and fidelities exceeding 99.99% across a wide range of noise strengths. Our work provides new insights into the geometric nature of noisy quantum dynamics and paves the way for developing strategies to dynamically correct quantum errors.

DOI: 10.1103/physrevapplied.23.054002

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