Interplay between altermagnetic order and crystal symmetry probed using magnetotransport in epitaxial altermagnet MnTe

TL;DR

This study investigates how altermagnetic order interacts with crystal symmetry in MnTe thin films, revealing controllable anomalous Hall effects and orientation-dependent electronic responses, advancing understanding for future spintronic devices.

Contribution

It provides the first detailed experimental link between altermagnetic order and crystal symmetry through magnetotransport measurements in epitaxial MnTe films.

Findings

Observation of spontaneous anomalous Hall effect in MnTe

Control of Hall response via magnetic field and crystallographic angle

Dependence of electronic responses on Nél vector and crystal orientation

Abstract

Altermagnets are a new class of magnetic materials characterized by fully compensated spins arranged in alternating local structures, allowing for spin-split bands similar to those found in ferromagnets without net magnetism. Recently, MnTe has emerged as a prototypical altermagnetic material exhibiting spin-polarized electronic bands and anomalous transport phenomena. Although recent work has explored the magnetic and structural properties of MnTe, detailed experimental investigations into the relationship between altermagnetic order and crystal symmetry are lacking. Here, we report the relationship between altermagnetic order and crystal symmetry by investigating magnetotransport properties of MnTe epitaxial altermagnetic thin films grown by molecular beam epitaxy. We observe a spontaneous anomalous Hall effect and show the control of Hall response with the altermagnetic order using the magnetic field and the crystallographic angle dependence. Detailed measurements establish that both the longitudinal and transverse electronic responses depend on the relative orientation of the applied current and N\'eel vector as well as on the crystal orientation and altermagnetic order. These results provide new insights into the interplay between crystal symmetry and altermagnetism for future device applications.