{ "id": "2407.21098", "version": "v1", "published": "2024-07-30T18:00:01.000Z", "updated": "2024-07-30T18:00:01.000Z", "title": "Topological transition as a percolation of the Berry curvature", "authors": [ "Han-Byul Kim", "Taewon Yuk", "Sang-Jin Sin" ], "comment": "9pages, 9 figures", "categories": [ "cond-mat.mes-hall" ], "abstract": "We first study the importance of the sign of the Berry curvature in the Euler characteristic of the two-dimensional topological material with two bands. Then we report an observation of a character of the topological transition as a percolation of the sign of the Berry curvature. The Berry curvature F has peaks at the Dirac points, enabling us to divide the Brillouin zone into two regions depending on the sign of the F: one with the same sign with a peak and the other with the opposite sign. We observed that when the Chern number is non-zero, the oppositely signed regions are localized. In contrast, in the case of a trivial topology, the oppositely signed regions are delocalized dominantly. Therefore, the oppositely signed region will percolate under the topological phase transition from non-trivial to trivial. We checked this for several models including the Haldane model, the extended Haldane model, and the QWZ model. Our observation may serve as a novel feature of the topological phase transition.", "revisions": [ { "version": "v1", "updated": "2024-07-30T18:00:01.000Z" } ], "analyses": { "keywords": [ "berry curvature", "topological transition", "oppositely signed region", "topological phase transition", "percolation" ], "note": { "typesetting": "TeX", "pages": 9, "language": "en", "license": "arXiv", "status": "editable" } } }