α-MnTe and Magnons: A General Overview

Manganese telluride (MnTe) is a relatively well-studied material whose antiferromagnetic and semiconducting properties make it relevant for various applications, notably for spintronics. Renewed interest in its study arose with recent experimental observations comprising of the anomalous Hall effect [3], anisotropic magnetoresistance and of its altermagnetic character . The first part of the talk will provide an overview of our current understanding of the material.

In the second part, introduction to a magnonic physics with emphasis on a qualitative behaviour and general patterns will be given, starting with classical macrospin structure and spin wave picture, leading up to a linear spin wave theory (LSWT) and its predictions for magnon dispersion spectra. Lastly, results of two THz spectroscopy measurement of k = 0 (i.e. Γ-point) magnons in the presence of an external magnetic field will be discussed and analysed in the context of presented theoretical framework and MnTe hard-axis anisotropy determination will be demonstrated