Topological chiral modes in random scattering networks

Pierre Delplace

doi:10.21468/scipostphys.8.5.081

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arXiv · 1905.11194

Topological chiral modes in random scattering networks

Pierre Delplace

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Abstract

Using elementary graph theory, we show the existence of interface chiral modes in random oriented scattering networks and discuss their topological nature. For particular regular networks (e.g. L-lattice, Kagome and triangular networks), an explicit mapping with time-periodically driven (Floquet) tight-binding models is found. In that case, the interface chiral modes are identified as the celebrated anomalous edge states of Floquet topological insulators and their existence is enforced by a symmetry imposed by the associated network. This work thus generalizes these anomalous chiral states beyond Floquet systems, to a class of discrete-time dynamical systems where a periodic driving in time is not required.

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Pierre Delplace. 2019-05-27. Topological chiral modes in random scattering networks. https://doi.org/10.21468/scipostphys.8.5.081

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