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arXiv · 2306.05595

Twofold topological phase transitions induced by third-nearest-neighbor interactions in 1D chains

Yonatan Betancur-Ocampo·B. Manjarrez-Montañez·A. M. Martínez-Argüello·Rafael A. Méndez-Sánchez
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Abstract

Strong long-range hoppings up to third nearest neighbors may induce a topological phase transition in one-dimensional chains. Unlike the Su-Schrieffer-Heeger model, this transition from trivial to topological phase occurs with the emergence of a pseudospin valley structure and a twofold nontrivial topological phase. Within a tight-binding approach, these topological phases are analyzed in detail and it is shown that the low-energy excitations follow a modified Dirac equation, in which the dynamics of particles with positive and negative mass occur differently. An experimental realization in a one-dimensional elastic chain, where it is feasible to tune directly the third-nearest-neighbor hoppings, is proposed.

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Yonatan Betancur-Ocampo, B. Manjarrez-Montañez, A. M. Martínez-Argüello, Rafael A. Méndez-Sánchez. 2023-06-08. Twofold topological phase transitions induced by third-nearest-neighbor interactions in 1D chains. https://arxiv.org/abs/2306.05595

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