| Autor: |
Fan, Annan, Liang, Shi‐Dong |
| Předmět: |
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| Zdroj: |
Annalen der Physik; Apr2022, Vol. 534 Issue 4, p1-10, 10p |
| Abstrakt: |
A geometric criterion of the topological phase transition for non‐Hermitian systems is proposed, based on the length of the boundary of the bulk band in the complex energy plane for non‐Hermitian systems. For 1D systems, it is found that the topological phase transition occurs when the derivatives of the length with respect to parameters are discontinuous. For 2D systems, when the length is discontinuous, the topological phase transitions between the gapped and gapless phases occur. When the derivatives of the length with respect to parameters are discontinuous, the topological phase transition between the gapless and gapless phases occur. These nonanalytic behaviors of the length in the complex energy plane provide a signal to detect the topological phase transitions, which is demonstrated by the 1D non‐Hermitian Su–Schrieffer–Heeger model and the 2D non‐Hermitian Chern insulator model. This geometric criterion provides an efficient insight into the global topological invariant from a geometric local object in the complex energy plane for non‐Hermitian systems. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
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