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arXiv · 0907.0252

Localization in one-dimensional incommensurate lattices beyond the Aubry-André model

J. Biddle·B. Wang·D. J. Priour Jr.·S. Das Sarma
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Abstract

Localization properties of particles in one-dimensional incommensurate lattices without interaction are investigated with models beyond the tight-binding Aubry-André (AA) model. Based on a tight-binding t_1 - t_2 model with finite next-nearest-neighbor hopping t_2, we find the localization properties qualitatively different from those of the AA model, signaled by the appearance of mobility edges. We then further go beyond the tight-binding assumption and directly study the system based on the more fundamental single-particle Schrödinger equation. With this approach, we also observe the presence of mobility edges and localization properties dependent on incommensuration.

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J. Biddle, B. Wang, D. J. Priour Jr., S. Das Sarma. 2009-07-01. Localization in one-dimensional incommensurate lattices beyond the Aubry-André model. https://doi.org/10.1103/physreva.80.021603

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