2011/09/30 by Yaacov E. Kraus, Yoav Lahini, Zohar Ringel +2 · 2 citations
Physics and Astronomy · #cond-mat.mes-hall #cond-mat.mtrl-sci #physics.optics #quant-ph
paper · pdf · doi:10.1103/physrevlett.109.106402
published as Phys. Rev. Lett. 109, 106402 (2012) · 10 pages, 5 figures, 4 appendices
arxiv created 2012/09/17 · arxiv updated 2012/09/18
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.