Spin-valve-like magnetoresistance in a Ni-Mn-In thin film

Abstract

Spin valve devices, the resistive state of which is controlled by switching the magnetization of a free ferromagnetic layer with respect to a pinned ferromagnetic layer, rely on the scattering of electrons within the active medium to work. Here we demonstrate spin-valve-like effect in the Ni-Mn-In thin films, which consists of a ferromagnetic phase embedded in an antiferromagnetic matrix. Through transport and magnetic measurements, we confirm that scattering at the interfaces between the two phases gives rise to a unidirectional anisotropy and the spin-valve-like effect in this system. The magnitude of the spin-valve-like magnetoresistance (about 0.4% at 10 K) is stable within the temperature range of 10-400 K. The low- and high-resistance states cannot be destroyed even under a high magnetic field of 100 kOe. This finding opens up a way of realizing the spin valve effect in materials with competing ferromagnetic and antiferromagnetic interactions, where the interface between these phases acts as the active medium.