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arXiv · 1309.4558

Topological phases of generalized Su-Schrieffer-Heeger models

Linhu Li·Zhihao Xu·Shu Chen
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Abstract

We study the extended Su-Schrieffer-Heeger model with both the nearest-neighbor and next-nearest-neighbor hopping strengths being cyclically modulated and find the family of the model system exhibiting topologically nontrivial phases, which can be characterized by a nonzero Chern number defined in a two-dimensional space spanned by the momentum and modulation parameter. It is interesting that the model has a similar phase diagram as the well-known Haldane's model. We propose to use photonic crystal systems as the idea systems to fabricate our model systems and probe their topological properties. Some other models with modulated on-site potentials are also found to exhibit similar phase diagrams and their connection to the Haldane's model is revealed.

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Linhu Li, Zhihao Xu, Shu Chen. 2014-02-12. Topological phases of generalized Su-Schrieffer-Heeger models. https://doi.org/10.1103/physrevb.89.085111

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