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arXiv · 2501.18461

Probing non-equilibrium topological order on a quantum processor

M. Will·T. A. Cochran·E. Rosenberg·B. Jobst·N. M Eassa·P. Roushan·M. Knap·A. Gammon-Smith·F. Pollmann
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Abstract

Out-of-equilibrium phases in many-body systems constitute a new paradigm in quantum matter - they exhibit dynamical properties that may otherwise be forbidden by equilibrium thermodynamics. Among these non-equilibrium phases are periodically driven (Floquet) systems [1-5], which are generically difficult to simulate classically because of their high entanglement. Here we realize a Floquet topologically ordered state theoretically proposed in ref. [6], on an array of superconducting qubits. We image the characteristic dynamics of its chiral edge modes and characterize its emergent anyonic excitations. Devising an interferometric algorithm allows us to introduce and measure a bulk topological invariant to probe the dynamical transmutation of anyons for system sizes up to 58 qubits. Our work demonstrates that quantum processors can provide key insights into the thus-far largely unexplored landscape of highly entangled non-equilibrium phases of matter.

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M. Will, T. A. Cochran, E. Rosenberg, B. Jobst, N. M Eassa, P. Roushan, M. Knap, A. Gammon-Smith, F. Pollmann. 2025-01-30. Probing non-equilibrium topological order on a quantum processor. https://doi.org/10.1038/s41586-025-09456-3

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