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arXiv · 1301.5639

Topological Zero-Energy Modes in Gapless Commensurate Aubry-Andr\'e-Harper Models

Sriram Ganeshan·Kai Sun·S. Das Sarma
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Abstract

The Aubry-Andr\'e or Harper (AAH) model has been the subject of extensive theoretical research in the context of quantum localization. Recently, it was shown that one-dimensional quasicrystals described by the incommensurate AAH model has a nontrivial topology. In this Letter, we show that the commensurate off-diagonal AAH model is topologically nontrivial in the gapless regime and supports zero-energy edge modes. Unlike the incommensurate case, the nontrivial topology in the off-diagonal AAH model is attributed to the topological properties of the one-dimensional Majorana chain. We discuss the feasibility of experimental observability of our predicted topological phase in the commensurate AAH model.

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Sriram Ganeshan, Kai Sun, S. Das Sarma. 2013-01-23. Topological Zero-Energy Modes in Gapless Commensurate Aubry-Andr\'e-Harper Models. https://doi.org/10.1103/physrevlett.110.180403

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