OpenAlex ·

Direction-dependent magnetoelectric conductivity from dipolar topological semimetals

Firdous Haidar and Ipsita Mandal

Published
Source
OpenAlex
Published in
arXiv (Cornell University)
DOI
10.48550/arxiv.2609.26676
Original
Read it at the publisher
Topics
Atomic PhysicsOptics

Abstract

We compute the linear magnetoelectric conductivity of a two-band vortex nodal-ring (VNR) semimetal and a three-band Hopf semimetal (HSM) within the semiclassical Boltzmann formalism, in the relaxation-time approximation, for three inequivalent planar-Hall configurations, with the electric ($\boldsymbol E$) and magnetic ($\boldsymbol B$) fields oriented differently relative to the nodal-ring plane and the Berry-curvature (BC) dipole axis. Unlike Weyl and multifold semimetals with point-monopole BC flux, the HSM carries a single, point-like BC-dipole fixed at its node, while the VNR hosts a continuous ring of such sources around the nodal loop. Both have vanishing Chern numbers. Working consistently to cubic order in $\boldsymbol B$, we evaluate the Drude, BC, orbital-magnetic-moment (OMM), anomalous-Hall, and Lorentz-force contributions. In both systems, the dipolar BC and OMM activate out-of-plane and odd-in-$\boldsymbol B$ in-plane response-channels that are symmetry-forbidden for a BC-monopole. Mirror symmetry confines the odd longitudinal terms to $B_z$, the field component along the dipole axis. The internode-scattering conductivity of the HSM vanishes identically, since the dipolar BC and OMM are even in momentum and no charge is pumped between two conjugate Hopf nodes, which carry oppositely oriented BC-dipoles. Comparisons with a $\mathcal{PT}$-broken gapped nodal-ring and a pseudospin-1 triple-point semimetal confirm the dipolar-BC origin of these features.

The authors’ abstract, as arXiv lists it. arXiv’s listings, abstracts included, are free for anyone to reuse.

Read it on ReadSearch

Each opens after you create an account, and brings you back to this paper.

Already a reader? Sign in

All new papers in Atomic Physics

Get the few papers worth your time in Atomic Physics every morning.

ReadSearch reads the new papers in your field each day and brings you the few worth reading, each with its key finding in a sentence.

Papers belong to their authors and publishers; every page here links to the original. All research topics