Anisotropic transport properties and high-mobility of charge carriers of antiferromagnetic GdAgSb2

Abstract

We report detailed magnetic and magnetotransport properties of single-crystalline GdAgSb2 antiferromagnet. The electronic transport properties show metallic behavior along with large, anisotropic, and non-saturating magnetoresistance (MR) in transverse experimental configuration. At 2 K and 9 T, the value of MR reaches as high as ∼1.8×103%. The anisotropic MR along with additional features for applied magnetic field along some specific crystallographic directions reveal the quasi-two-dimensional nature of the Fermi surface of GdAgSb2. Hall resistivity confirms the presence of two types of charge carriers. The high carrier mobilities (∼1.2×104 cm2 V−1 s−1) and nearly-compensated electron and hole-density (∼1019 cm−3) could be responsible for the large transverse MR in GdAgSb2. We have also observed the de Haas–van Alphen oscillations in the magnetization measurements below 7 K. Furthermore, the robust planar Hall effect, which persists up to high temperatures, could indicate the nontrivial nature of the electronic band structure for GdAgSb2.