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

Abstract

We study the origin of large topological Hall effect in the single-crystalline EuCd${}_2$Sb${}_2$, which orders antiferromagnetically at the Néel temperature $T_{\mathrm{N}}=7.4$ 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 $T_{\mathrm{N}}$, Weyl states are the main sources of large momentum-space Berry curvature, though their formation mechanisms differ in these two temperature ranges. Below $T_{\mathrm{N}}$, breaking of $C_3$ symmetry generates Dirac points that split into Weyl nodes in applied magnetic field, whereas above $T_{\mathrm{N}}$, strong spin fluctuations can induce Weyl states. The third contribution, which occurs below $T_{\mathrm{N}}$, arises from scalar spin chirality developing within antiferromagnetic domain walls, which generates a real-space Berry curvature.

10 pages, 6 figures, Supplemental Material has 4 pages and 5 figures

References in corpus (15)

• Spin fluctuation induced Weyl semimetal state in the paramagnetic phase of EuCd${}_2$As${}_2$
• Intrinsic anomalous Hall effect in Ni-substituted magnetic Weyl semimetal Co3Sn2S2
• Topological spiral magnetism in the Weyl semimetal SmAlSi
• Field-induced Topological Hall effect in antiferromagnetic axion insulator candidate EuIn${}_2$As${}_2$
• Dipolar Magnetic Interactions and A-type Antiferromagnetic Order in the Zintl Phase Insulator EuZn2P2
• Anisotropy of the magnetic and transport properties in EuZn${}_2$As${}_2$
• Anomalous Hall effect and negative longitudinal magnetoresistance in half-Heusler topological semimetal candidates TbPtBi and HoPtBi
• Topological Hall Effect Driven by Short-Range Magnetic Orders in EuZn${}_2$As${}_2$
• A-type antiferromagnetic order in semiconducting EuMg${}_2$Sb${}_2$ single crystals
• Large unconventional anomalous Hall effect arising from spin chirality within domain walls of an antiferromagnet EuZn${}_2$Sb${}_2$
• Maximizing intrinsic anomalous Hall effect by controlling the Fermi level in simple Weyl semimetal films
• Berry curvature derived negative magnetoconductivity observed in type-II magnetic Weyl semimetal films
• Nature of field-induced transitions and hysteretic magnetoresistance in non-collinear antiferromagnet EuIn2As2
• Anomalous Hall effect in the antiferromagnetic Weyl semimetal SmAlSi
• Origin of the large topological Hall effect in the EuCd${}_2$Sb${}_2$ antiferromagnet

Cited by in corpus (1)

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