Topological Hall effect in the antiferromagnetic Dirac semimetal EuAgAs

Abstract

The non-trivial magnetic texture in real space gives rise to the intriguing phenomenon of topological Hall effect (THE), which is relatively less explored in topological semimetals. Here, we report large THE in the antiferromagnetic (AFM) state in single crystals of EuAgAs, an AFM Dirac semimetal. EuAgAs hosts AFM ground state below $T_N$ = 12 K with a weak ferromagnetic component. The in-plane isothermal magnetization below $T_N$ exhibits a weak metamagnetic transition. We also observe chiral anomaly induced positive longitudinal magnetoconductivity which indicates a Weyl fermion state under applied magnetic field. The first-principles calculations reveal that EuAgAs is an AFM Dirac semimetal with a pair of Dirac cones, and therefore, a Weyl semimetailic state can be realized under time-reversal symmetry breaking via an applied magnetic field. Our study establishes that EuAgAs is a novel system for exploiting the interplay of band topology and the topology of the magnetic texture.

Accepted for publication in Phys. Rev. B as a Letter

References in corpus (15)

• Robust formation of skyrmions and topological Hall effect in epitaxial thin films of MnSi
• Néel-type skyrmion lattice in tetragonal polar magnet VOSe${}_2$O${}_5$
• Topological Magnetic Phase in the Candidate Weyl Semimetal CeAlGe
• Tunable magnon Weyl points in ferromagnetic pyrochlores
• Weak Antilocalization Effect and Noncentrosymmetric Superconductivity in a Topologically Nontrivial Semimetal LuPdBi
• Controllable chirality-induced geometrical Hall effect in a frustrated highly-correlated metal
• Magnetic ordering and dense Kondo behaviour in EuFe${}_2$P${}_2$
• Magnetotransport properties and giant anomalous Hall angle in half-Heusler compound TbPtBi
• Itinerant and local-moment magnetism in EuCr2As2 single crystals
• Magnetotransport properties of the topological nodal-line semimetal CaCdSn
• Transition from semiconducting to metallic-like conducting and weak antilocalization effect in single crystals of LuPtSb
• Thermal and gravitational chiral anomaly induced magneto-transport in Weyl semimetals
• Ferromagnetic state above room temperature in a proximitized topological Dirac semimetal
• Experimental and theoretical study of the correlated compound YbCdSn: Evidence for large magnetoresistance and mass enhancement
• Electronic properties of topological insulator candidate CaAgAs

Cited by in corpus (1)

• Multiple magnetism controlled topological states in EuAgAs