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arXiv · 1606.07651

Topological Heat Transport and Symmetry-Protected Boson Currents

Ángel Rivas·Miguel A. Martin-Delgado
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Abstract

The study of non-equilibrium properties in topological systems is of practical and fundamental importance. Here, we analyze the stationary properties of a two-dimensional bosonic Hofstadter lattice coupled to two thermal baths in the quantum open-system formalism. Novel phenomena appear like chiral edge heat currents that are the out-of-equilibrium counterparts of the zero-temperature edge currents. They support a new concept of dissipative symmetry-protection, where a set of discrete symmetries protects topological heat currents, differing from the symmetry-protection devised in closed systems and zero-temperature. Remarkably, one of these currents flows opposite to the decreasing external temperature gradient. As the starting point, we consider the case of a single external reservoir already showing prominent results like thermal erasure effects and topological thermal currents. Our results are experimentally accessible with platforms like photonics systems and optical lattices.

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Ángel Rivas, Miguel A. Martin-Delgado. 2016-06-24. Topological Heat Transport and Symmetry-Protected Boson Currents. https://doi.org/10.1038/s41598-017-06722-x

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