High-throughput screening of altermagnetic materials
Romakanta Bhattarai, Peter Minch, Trevor David Rhone
Abstract
Altermagnets are a special class of magnetic materials that exhibit an unusual combination of features from both ferromagnets and antiferromagnets. That is, they have zero net magnetization (i.e., antiferromagnetic properties) with electronic bands that are not Kramers spin degenerate (i.e., ferromagnetic behavior). This offers the possibility of generating spin-polarized currents without the stray magnetic fields associated with ferromagnets, making them ideal candidates for potential applications in quantum computing and energy-efficient spintronic devices. In this work, we investigate altermagnets of the form ${{\mathrm{A}}_{2}\mathrm{X}}^{i}{\mathrm{X}}^{ii}$ based on $\ensuremath{\alpha}\text{\ensuremath{-}}{\mathrm{Mn}}_{2}{\mathrm{Te}}_{2}$, a well-known altermagnet, using high-throughput density functional theory calculations. Promising candidates are determined by analyzing their preferred magnetic ordering and spin degeneracy. The magnetic ground states of the altermagnet candidates are then confirmed using spin-spiral calculations. Based on the presence of Kramers degeneracy in the band structure, which is linked to crystal symmetry, we classify the candidate structures as $d$-wave and $g$-wave altermagnets, as well as fully compensated ferrimagnets.