Occupation of topological Floquet bands in open systems

Thomas Iadecola; Titus Neupert; Claudio Chamon

doi:10.1103/physrevb.91.235133

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arXiv · 1502.05047

Occupation of topological Floquet bands in open systems

Thomas Iadecola·Titus Neupert·Claudio Chamon

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Abstract

Floquet topological insulators are noninteracting quantum systems that, when driven by a time-periodic field, are described by effective Hamiltonians whose bands carry nontrivial topological invariants. A longstanding question concerns the possibility of selectively populating one of these effective bands, thereby maximizing the system's resemblance to a static topological insulator. We study such Floquet systems coupled to a zero-temperature thermal reservoir that provides dissipation. We find that the resulting electronic steady states are generically characterized by a finite density of excitations above the effective ground state, even when the driving has a small amplitude and/or large frequency. We discuss the role of reservoir engineering in mitigating this problem.

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Thomas Iadecola, Titus Neupert, Claudio Chamon. 2015-06-04. Occupation of topological Floquet bands in open systems. https://doi.org/10.1103/physrevb.91.235133

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