Bulk-edge correspondence in the trimer Su-Schrieffer-Heeger model
| Autor: | Anastasiadis, Adamantios, Styliaris, Georgios, Chaunsali, Rajesh, Theocharis, Georgios, Diakonos, Fotios K. |
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| Rok vydání: | 2022 |
| Předmět: | |
| Zdroj: | Phys. Rev. B 106, 085109 (2022) |
| Druh dokumentu: | Working Paper |
| DOI: | 10.1103/PhysRevB.106.085109 |
| Popis: | A remarkable feature of the trimer Su-Schrieffer-Heeger (SSH3) model is that it supports localized edge states. Although Zak's phase remains quantized for the case of a mirror-symmetric chain, it is known that it fails to take integer values in the absence of this symmetry and thus it cannot play the role of a well-defined bulk invariant in the general case. Attempts to establish a bulk-edge correspondence have been made via Green's functions or through extensions to a synthetic dimension. Here we propose a simple alternative for SSH3, utilizing the previously introduced sublattice Zak's phase, which also remains valid in the absence of mirror symmetry and for non-commensurate chains. The defined bulk quantity takes integer values, is gauge invariant, and can be interpreted as the difference of the number of edge states between a reference and a target Hamiltonian. Our derivation further predicts the exact corrections for finite open chains, is straightforwadly generalizable, and invokes a chiral-like symmetry present in this model. Comment: 11 pages + 5 pages Appendix, 9 figures, comments welcome |
| Databáze: | arXiv |
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