Magnetic control of Weyl nodes and wave packets in three-dimensional warped semimetals

Bruno Focassio; Gabriel R. Schleder; Adalberto Fazzio; Rodrigo B. Capaz; Pedro V. Lopes; Jaime Ferreira; Carsten Enderlein; Marcello B. Silva Neto

arXiv · 2401.06282

Magnetic control of Weyl nodes and wave packets in three-dimensional warped semimetals

Bruno Focassio·Gabriel R. Schleder·Adalberto Fazzio·Rodrigo B. Capaz·Pedro V. Lopes·Jaime Ferreira·Carsten Enderlein·Marcello B. Silva Neto

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Abstract

We investigate the topological phase transitions driven by band warping and a transverse magnetic field, for three-dimensional Weyl semimetals. First, we use the Chern number as a mathematical tool to derive the topological phase diagram. Next, we associate each of the topological sectors to a given angular momentum state of a rotating wave packet. Then we show how the position of the Weyl nodes can be manipulated by a transverse external magnetic field that ultimately quenches the wave packet rotation, first partially and then completely, thus resulting in a sequence of field-induced topological phase transitions. Finally, we calculate the current-induced magnetization and the anomalous Hall conductivity of a prototypical warped Weyl material. Both observables reflect the topological transitions associated with the wave packet rotation and can help to identify the elusive 3D quantum anomalous Hall effect in three-dimensional, warped Weyl materials.

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Bruno Focassio, Gabriel R. Schleder, Adalberto Fazzio, Rodrigo B. Capaz, Pedro V. Lopes, Jaime Ferreira, Carsten Enderlein, Marcello B. Silva Neto. 2024-01-11. Magnetic control of Weyl nodes and wave packets in three-dimensional warped semimetals. https://arxiv.org/abs/2401.06282

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