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arXiv · 2112.07697

Dirac States in an Inclined Two-Dimensional Su-Schrieffer-Heeger Model

Chang-An Li·Sang-Jun Choi·Song-Bo Zhang·Björn Trauzettel
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Abstract

We propose to realize Dirac states in an inclined two-dimensional Su-Schrieffer-Heeger model on a square lattice. We show that a pair of Dirac points protected by space-time inversion symmetry appear in the semimetal phase. The locations of these Dirac points are not pinned to any high-symmetry points of the Brillouin zone but are tunable through parameter modulations. Interestingly, the merging of two Dirac points undergoes a topological phase transition that leads to either a weak topological insulator or a nodal-line semimetal. We provide a systematic analysis of these topological phases from both bulk and boundary perspectives combined with symmetry arguments. We also discuss feasible experimental platforms to realize our model.

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Chang-An Li, Sang-Jun Choi, Song-Bo Zhang, Björn Trauzettel. 2021-12-14. Dirac States in an Inclined Two-Dimensional Su-Schrieffer-Heeger Model. https://doi.org/10.1103/physrevresearch.4.023193

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