Metallic d-wave altermagnetism in WFeB: a platform for electrically switchable perpendicular spin-splitter response

TL;DR

This paper introduces WFeB as a metallic altermagnet with switchable spin-splitter response, demonstrating its potential for electrically controlled spin-current generation in spintronic applications.

Contribution

It reports the synthesis, magnetic characterization, and symmetry analysis of WFeB, establishing it as a platform for electrically switchable altermagnetic spin-splitter response.

Findings

WFeB exhibits a nonrelativistic spin splitting of ~100 meV.

Symmetry analysis enables deterministic switching of the Nél vector by current.

WFeB supports a strong spin-splitter transport response despite modest band splitting.

Abstract

We report the synthesis and magnetic characterization of WFeB and identify it as a metallic d-wave altermagnet representative of a broader TiNiSi-type family. Neutron diffraction, M\"ossbauer spectroscopy, and magnetometry establish a collinear altermagnetic ordering confirmed by first-principles calculations. The electronic structure shows a nonrelativistic spin splitting of approximately 100 meV, but it also supports a strong spin-splitter transport response. This demonstrates that efficient spin-current generation can occur even with such modest band splitting. Symmetry analysis shows that selected film orientations permit deterministic switching of the N\'eel vector by current-induced staggered torques, enabling electrical control of a perpendicular spin-splitter response. These results establish WFeB and related TiNiSi-type antiferromagnets as a platform for electrically switchable charge-to-spin conversion driven by altermagnetic symmetry.