Asymmetric Magnetoresistance and Topological Hall Effect in MnZnSb single crystal

Abstract

The realization of advanced spintronic phenomena in bulk materials offers a robust alternative to complex thin-film heterostructures. This study investigates the low-temperature magnetic and magnetotransport properties of bulk single-crystal MnZnSb, a ferromagnet with a Curie temperature (T_C​) of ~315 K. Comprehensive characterization reveals a complex magnetic ground state below 150 K, defined by the coexistence of ferromagnetic (FM) clusters within an antiferromagnetic (AFM) or weak ferrimagnetic (WFRI) matrix. This state, stabilized by intrinsic features such as antisite disorder and kinetic arrest, creates a network of internal magnetic interfaces. Consequently, the material exhibits a pronounced spin-valve-like magnetoresistance (SVMR), an effect exceptionally rare in bulk systems, driven by spin-dependent scattering across these interfaces. Concurrently, we uncover a significant topological Hall effect (THE), with a topological Hall resistivity ( )  of ~440 nΩ cm at 5 K, contradicting earlier reports of its absence. The SVMR and THE are presented as complementary transport signatures of the non-trivial spin textures arising from the material's intrinsic magnetic inhomogeneities. These findings demonstrate that complex, heterostructure-like spintronic functionalities can emerge from phase competition in a single bulk material, opening new avenues for device design.