Optical conductivity of multi-Weyl node semimetals due to electromagnetic and axial pseudogauge fields

Journal Article · 08 June 2023 · Annals of Physics

DOI: https://doi.org/10.1016/j.aop.2023.169380 · OSTI ID:1985857

Schmeltzer, D. ^[1]; Saxena, Avadh Behari  ^[2]

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1. City College of New York, NY (United States)
2. Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)

Here, we compute the optical conductivity of a multi-Weyl semimetal in the presence of electromagnetic and axial fields. In the first part of the paper we use a U(1) gauge field to compute the current of a multi-Weyl semimetal. The current is used in the computation of the optical conductivity within the Kubo-Matsubara formalism. We consider a multi-Weyl semimetal with two nodal points in the z-direction. The multi-Weyl semimetal has a width D in the transverse direction which is smaller than the length L in the longitudinal direction. Due to the width D we replace the model by a sum of transverse modes in 1+1 dimensions. We then regularize the model in 1+1 dimensions. The nodal points are responsible for a constant axial field and a static anomalous Hall effect. In the second part we study the effect of dynamic axial fields. An elastic deformation couples to the two electronic chiralities, and represents the axial pseudogauge field $$\vec{a}$$⁵. As a consequence, the system is excited by two kinds of field, the electromagnetic one and the axial srain field. For a Weyl system this is represented by the triangle diagram, which is responsible for the anomalous Hall effect. We can obtain the anomalous Hall effect also by a chiral transformation in 1+1 dimensions using regularization. The chiral transformation modifies the path integration measure and is the source of the induced anomalous Hall effect. The latter is controlled by a combination of strain waves and electromagnetic fields.

• Research Organization: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
• Sponsoring Organization: USDOE Laboratory Directed Research and Development (LDRD) Program; USDOE National Nuclear Security Administration (NNSA)
• Grant/Contract Number: 89233218CNA000001; AC52-06NA25396
• OSTI ID: 1985857
• Report Number(s): LA-UR-21-25129
• Journal Information: Annals of Physics, Journal Name: Annals of Physics Vol. 455; ISSN 0003-4916
• Publisher: ElsevierCopyright Statement
• Country of Publication: United States
• Language: English