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arXiv · 1109.5983

Topological States and Adiabatic Pumping in Quasicrystals

Yaacov E. Kraus·Yoav Lahini·Zohar Ringel·Mor Verbin·Oded Zilberberg
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Abstract

The unrelated discoveries of quasicrystals and topological insulators have in turn challenged prevailing paradigms in condensed-matter physics. We find a surprising connection between quasicrystals and topological phases of matter: (i) quasicrystals exhibit nontrivial topological properties and (ii) these properties are attributed to dimensions higher than that of the quasicrystal. Specifically, we show, both theoretically and experimentally, that one-dimensional quasicrystals are assigned two-dimensional Chern numbers and, respectively, exhibit topologically protected boundary states equivalent to the edge states of a two-dimensional quantum Hall system.We harness the topological nature of these states to adiabatically pump light across the quasicrystal. We generalize our results to higher-dimensional systems and other topological indices. Hence, quasicrystals offer a new platform for the study of topological phases while their topology may better explain their surface properties.

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cond-mat.mes-hallcond-mat.mtrl-sciphysics.opticsquant-ph

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Yaacov E. Kraus, Yoav Lahini, Zohar Ringel, Mor Verbin, Oded Zilberberg. 2011-09-27. Topological States and Adiabatic Pumping in Quasicrystals. https://doi.org/10.1103/physrevlett.109.106402

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