Antiferromagnetic (AF) materials are attracting increasing interest for research in magnetic physics and spintronics. Here, we report a controllable synthesis of room-temperature AF α-MnTe nanocrystals (Néel temperature ∼307 K) via the molten-salt-assisted chemical vapor deposition method. The growth kinetics are investigated regarding the dependence of flake dimension and macroscopic shape on growth time and temperature. The high crystalline quality and atomic structure are confirmed by various crystallographic characterization means. Cryogenic magneto-transport measurements reveal anisotropic magnetoresistance (MR) response and complicated dependence of MR on temperature, owing to the subtle competition among multiple scattering mechanisms of thermally excited magnetic disorders (magnon drag), magnetic transition, and thermally populated lattice phonons. Overall positive MR behavior with two transitions in magnitude is observed when out-of-plane external magnetic field (B) is applied, while a transition from negative to positive MR response is recorded when in-plane B is applied. The rich magnetic transport properties render α-MnTe a promising material for exploiting functional components in magnetic devices.

The anisotropy contributions in epitaxial Fe/MnPd bilayers were analyzed in this study. It was found that due to ferromagnetic-antiferromagnetic interfacial exchange coupling, large uniaxial and cubic anisotropy contributions are also induced, in addition to the unidirectional anisotropy. These contributions play an essential role in the magnetization reversal process of the system, in which unusual reversal processes were found upon some fields orientations.

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