Structure and Properties of Antiferromagnetic Dirac Semi-Metal EuZnSb2

Abstract

A EuZnSb₂ antiferromagnetic (AFM) semi metal with a P4/nmm space group (No. 129) is synthesized using the Sb-flux method. The magnetic properties, specific heat, and resistivity of the EuZnSb₂ single crystals are analyzed. The magnetic and specific heat properties indicate an antiferromagnetic order of Eu²⁺ with T_N ~ 20 K. The magnetic field is observed to suppress the AFM transition of Eu²⁺ and the magnetic susceptibility vs. temperature curves exhibit differences when the magnetic field is applied along the ab-plane and c-axis of EuZnSb₂ single crystal, reflecting a weak in-plane anisotropy of Eu²⁺. When the temperature is below 20 K, a spin‒flop transition of the AFM order appears at approximately 1.6 T. The electronic transport measurements indicate that a EuZnSb₂ single crystal exhibits metallic properties and an extremely unsaturated positive MR effect. A twofold period of anisotropic magnetoresistance is observed, indicating that the resistivity characteristics correlate with the magnetic field intensity and the angle between the magnetic field direction and the crystallographic axis direction. These studies contribute to enriching the magnetic, specific thermal, and electrical transport properties of EuZnSb₂. These results also provide valuable information for further research on other AFM materials.