Hidden Weyl points in centrosymmetric paramagnetic metals


Date

2017-03-02

Publication Type

Journal Article

ETH Bibliography

yes

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Data

Abstract

The transition metal dipnictides TaAs2, TaSb2, NbAs2 and NbSb2 have recently sparked interest for exhibiting giant magnetoresistance. While the exact nature of the magnetoresistance in these materials is still under active investigation, there are experimental results indicating that it is of the anisotropic negative variety. We study the effect of magnetic fields on the band structure topology of these materials by applying Zeeman splitting. In the absence of a magnetic field, we find that the materials are weak topological insulators, which is in agreement with previous studies. When the magnetic field is applied, we find that type-II Weyl points form. This result is found first from a symmetry argument, and then numerically for a ${\bf{k}}\cdot {\bf{p}}$ model of TaAs2 and a tight-binding model of NbSb2. This effect could be of help in the search for an explanation of the anomalous magnetoresistance in these materials.

Publication status

published

Editor

Book title

Volume

19

Pages / Article No.

35001

Publisher

IOP Publishing

Event

Edition / version

Methods

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Geographic location

Date collected

Date created

Subject

Chiral anomaly; Magnetoresistance; Weyl semimetal; Zeeman splitting

Organisational unit

03622 - Troyer, Matthias (ehemalig) / Troyer, Matthias (former) check_circle

Notes

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