Altermagnets exhibit momentum-dependent spin splitting despite having zero net magnetization. This enables a spin-splitter effect in which an external electric field generates transverse spin currents by separating oppositely polarized carriers. Here, we develop a unified semiclassical theory of linear extrinsic spin-splitter currents, incorporating impurity-induced side-jump and skew-scattering contributions, and apply it to the d-wave altermagnet \ch{FeSb2}. We demonstrate that asymmetric impurity scattering provides a dominant channel for spin-splitter currents. Remarkably, the resulting extrinsic spin conductivity is time-reversal even, in contrast to previously studied spin-splitter responses arising from symmetric scattering.
@article{arxiv.2602.23273,
title = {Extrinsic Spin Splitter Currents in Altermagnets},
author = {Sanjay Sarkar and Sayan Sarkar and Amit Agarwal},
journal= {arXiv preprint arXiv:2602.23273},
year = {2026}
}