Origin of the large topological Hall effect in the EuCd$_2$Sb$_2$ antiferromagnet

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Gul, Faheem, Pavlosiuk, Orest, Romanova, Tetiana, Kaczorowski, Dariusz, Wiśniewski, Piotr
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866910029652688896
author Gul, Faheem
Pavlosiuk, Orest
Romanova, Tetiana
Kaczorowski, Dariusz
Wiśniewski, Piotr
author_facet Gul, Faheem
Pavlosiuk, Orest
Romanova, Tetiana
Kaczorowski, Dariusz
Wiśniewski, Piotr
contents We study the origin of large topological Hall effect in the single-crystalline EuCd$_2$Sb$_2$, which orders antiferromagnetically at the Néel temperature $T_{\rm N}=7.4$ K. Measurements of magnetoresistance and Hall resistivity disclose anomalies that evolve with temperature and magnetic field, closely tracking the magnetization process. Analysis of these data identifies three possible mechanisms responsible for the enhanced Berry curvature driving the observed topological Hall effect. Below and above $T_{\rm N}$, Weyl states are the main sources of large momentum-space Berry curvature, though their formation mechanisms differ in these two temperature ranges. Below $T_{\rm N}$, breaking of $C_{3}$ symmetry generates Dirac points that split into Weyl nodes in applied magnetic field, whereas above $T_{\rm N}$, strong spin fluctuations can induce Weyl states. The third contribution, which occurs below $T_{\rm N}$, arises from scalar spin chirality developing within antiferromagnetic domain walls, which generates a real-space Berry curvature.
format Preprint
id arxiv_https___arxiv_org_abs_2511_17445
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Origin of the large topological Hall effect in the EuCd$_2$Sb$_2$ antiferromagnet
Gul, Faheem
Pavlosiuk, Orest
Romanova, Tetiana
Kaczorowski, Dariusz
Wiśniewski, Piotr
Materials Science
We study the origin of large topological Hall effect in the single-crystalline EuCd$_2$Sb$_2$, which orders antiferromagnetically at the Néel temperature $T_{\rm N}=7.4$ K. Measurements of magnetoresistance and Hall resistivity disclose anomalies that evolve with temperature and magnetic field, closely tracking the magnetization process. Analysis of these data identifies three possible mechanisms responsible for the enhanced Berry curvature driving the observed topological Hall effect. Below and above $T_{\rm N}$, Weyl states are the main sources of large momentum-space Berry curvature, though their formation mechanisms differ in these two temperature ranges. Below $T_{\rm N}$, breaking of $C_{3}$ symmetry generates Dirac points that split into Weyl nodes in applied magnetic field, whereas above $T_{\rm N}$, strong spin fluctuations can induce Weyl states. The third contribution, which occurs below $T_{\rm N}$, arises from scalar spin chirality developing within antiferromagnetic domain walls, which generates a real-space Berry curvature.
title Origin of the large topological Hall effect in the EuCd$_2$Sb$_2$ antiferromagnet
topic Materials Science
url https://arxiv.org/abs/2511.17445