Approximate half-integer quantization in anomalous planar transport in $d$-wave altermagnets

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Korrapati, Srimayi, Nandy, Snehasish, Tewari, Sumanta
Natura: Preprint
Pubblicazione: 2025
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866914177791033344
author Korrapati, Srimayi
Nandy, Snehasish
Tewari, Sumanta
author_facet Korrapati, Srimayi
Nandy, Snehasish
Tewari, Sumanta
contents We investigate anomalous planar transport phenomena in a recently identified class of collinear magnetic materials known as $d$-wave altermagnets. The anomalous planar effects manifest in a configuration when the applied electric field/temperature gradient, magnetic field, and the measured Hall voltage are all co-planar, but the planar magnetic field is instrumental in breaking $\hat{C}_{4z}\hat{\mathcal{T}}$ symmetry of the $d$-wave altermagnet, where $\hat{\mathcal{T}}$ is the time reversal operator, resulting in a Zeeman gap at a shifted Dirac node and a nonzero Berry curvature monopole. We demonstrate that these systems exhibit nearly half-quantized anomalous planar Hall and planar thermal Hall effects at low temperatures that persist over a range of magnetic fields. The angular dependence of the planar transport reveals a $\cos2ϕ$ dependence on the magnetic field direction, where $ϕ$ is the azimuthal angle made by the magnetic field. We also discuss the anomalous planar Nernst effect, or transverse thermopower, and demonstrate that the Nernst conductivity peaks when the chemical potential lies just outside the induced Zeeman gap and vanishes within the gap. We further explore the dependence of all three coefficients on the polar and the azimuthal angle of the magnetic field when it is rotated in the full $3D$ space. Our results reveal the presence of approximately half-quantized anomalous planar thermal Hall plateau for a range of in-plane magnetic fields without requiring topological superconductivity and conducting Majorana modes, and can be probed in experiments in $d$-wave altermagnets.
format Preprint
id arxiv_https___arxiv_org_abs_2506_24122
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Approximate half-integer quantization in anomalous planar transport in $d$-wave altermagnets
Korrapati, Srimayi
Nandy, Snehasish
Tewari, Sumanta
Mesoscale and Nanoscale Physics
Other Condensed Matter
We investigate anomalous planar transport phenomena in a recently identified class of collinear magnetic materials known as $d$-wave altermagnets. The anomalous planar effects manifest in a configuration when the applied electric field/temperature gradient, magnetic field, and the measured Hall voltage are all co-planar, but the planar magnetic field is instrumental in breaking $\hat{C}_{4z}\hat{\mathcal{T}}$ symmetry of the $d$-wave altermagnet, where $\hat{\mathcal{T}}$ is the time reversal operator, resulting in a Zeeman gap at a shifted Dirac node and a nonzero Berry curvature monopole. We demonstrate that these systems exhibit nearly half-quantized anomalous planar Hall and planar thermal Hall effects at low temperatures that persist over a range of magnetic fields. The angular dependence of the planar transport reveals a $\cos2ϕ$ dependence on the magnetic field direction, where $ϕ$ is the azimuthal angle made by the magnetic field. We also discuss the anomalous planar Nernst effect, or transverse thermopower, and demonstrate that the Nernst conductivity peaks when the chemical potential lies just outside the induced Zeeman gap and vanishes within the gap. We further explore the dependence of all three coefficients on the polar and the azimuthal angle of the magnetic field when it is rotated in the full $3D$ space. Our results reveal the presence of approximately half-quantized anomalous planar thermal Hall plateau for a range of in-plane magnetic fields without requiring topological superconductivity and conducting Majorana modes, and can be probed in experiments in $d$-wave altermagnets.
title Approximate half-integer quantization in anomalous planar transport in $d$-wave altermagnets
topic Mesoscale and Nanoscale Physics
Other Condensed Matter
url https://arxiv.org/abs/2506.24122