Classification of topological insulators and superconductors out of equilibrium

Max McGinley; Nigel R. Cooper

doi:10.1103/physrevb.99.075148

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arXiv · 1811.00889

Classification of topological insulators and superconductors out of equilibrium

Max McGinley·Nigel R. Cooper

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Abstract

We establish the existence of a topological classification of many-particle quantum systems undergoing unitary time evolution. The classification naturally inherits phenomenology familiar from equilibrium -- it is robust against disorder and interactions, and exhibits a non-equilibrium bulk-boundary correspondence, which connects bulk topological properties to the entanglement spectrum. We explicitly construct a non-equilibrium classification of non-interacting fermionic systems with non-spatial symmetries in all spatial dimensions (the `ten-fold way'), which differs from its equilibrium counterpart. Direct physical consequences of our classification are discussed, including important ramifications for the use of topological zero-energy bound states in quantum information technologies.

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Max McGinley, Nigel R. Cooper. 2019-02-25. Classification of topological insulators and superconductors out of equilibrium. https://doi.org/10.1103/physrevb.99.075148

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