An Operational Definition of Topological Order

Abstract

The unrivaled robustness of topologically ordered states of matter against perturbations has immediate applications in quantum computing and quantum metrology, yet their very existence poses a challenge to our understanding of phase transitions. However, a comprehensive understanding of what actually constitutes topological order is still lacking. Here we show that one can interpret topological order as the ability of a system to perform topological error correction. We find that this operational approach corresponding to a measurable both lays the conceptual foundations for previous classifications of topological order and also leads to a successful classification in the hitherto inaccessible case of topological order in open quantum systems. We demonstrate the existence of topological order in open systems and their phase transitions to topologically trivial states. Our results demonstrate the viability of topological order in nonequilibrium quantum systems and thus substantially broaden the scope of possible technological applications.

7 pages, 5 figures; Supplementary - 5 pages, 3 figures

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Cited by in corpus (8)

• Driven-dissipative criticality within the discrete truncated Wigner approximation
• Enhancing Detection of Topological Order by Local Error Correction
• Stable Symmetry-Protected Topological Phases in Systems with Heralded Noise
• Error-correction properties of an interacting topological insulator
• Exact Quantum Algorithms for Quantum Phase Recognition: Renormalization Group and Error Correction
• Learning of error statistics for the detection of quantum phases
• Kibble-Zurek mechanism and errors of gapped quantum phases
• Topological Phase Transitions Induced by Varying Topology and Boundaries in the Toric Code