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arXiv · 2108.06994

Topological hybrid semimetal phases and anomalous Hall effects in a three dimensional magnetic topological insulator

M. N. Chen·W. C. Chen·Yu Zhou
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Abstract

In this work, we propose a ferromagnetic Bi$_2$Se$_3$ as a candidate to hold the coexistence of Weyl- and nodal-line semimetal phases, which breaks the time reversal symmetry. We demonstrate that the type-I Weyl semimetal phase, type-I-, type-II- and their hybrid nodal-line semimetal phases can arise by tuning the Zeeman exchange field strength and the Fermi velocity. Their topological responses under U(1) gauge field are also discussed. Our results raise a new way for realizing Weyl and nodal-line semimetals and will be helpful in understanding the topological transport phenomena in three-dimensional material systems.

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M. N. Chen, W. C. Chen, Yu Zhou. 2021-08-16. Topological hybrid semimetal phases and anomalous Hall effects in a three dimensional magnetic topological insulator. https://doi.org/10.1088/1674-1056/abff29

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