Robust spin splitting and fermiology in a layered altermagnet
Abstract
Altermagnetism defies conventional classifications of collinear magnetic phases, standing apart from ferromagnetism and antiferromagnetism with its unique combination of spin-dependent symmetries, net-zero magnetization, and anomalous Hall transport. Although altermagnetic states have been realized experimentally, their integration into functional devices has been hindered by the structural rigidity and poor tunability of existing materials. First, through cobalt intercalation of the superconducting 2H-NbSe polymorph, we induce and stabilize a robust altermagnetic phase and using both theory and experiment, we directly observe the lifting of Kramers degeneracy. Additionally, we present spectroscopic insight into a previously hinted low-temperature phase, and provide evidence of its electronic origin. While shedding light on overlooked aspects of altermagnetism, these findings open pathways to spin-based technologies and lay a foundation for advancing the emerging field of altertronics.
Cite
@article{arxiv.2502.20010,
title = {Robust spin splitting and fermiology in a layered altermagnet},
author = {Alessandro De Vita and Chiara Bigi and Davide Romanin and Matthew D. Watson and Vincent Polewczyk and Marta Zonno and François Bertran and My Bang Petersen and Federico Motti and Giovanni Vinai and Manuel Tuniz and Federico Cilento and Mario Cuoco and Brian M. Andersen and Andreas Kreisel and Luciano Jacopo D'Onofrio and Oliver J. Clark and Mark T. Edmonds and Christopher Candelora and Muxian Xu and Siyu Cheng and Alexander LaFleur and Tommaso Antonelli and Giorgio Sangiovanni and Lorenzo Del Re and Ivana Vobornik and Jun Fujii and Fabio Miletto Granozio and Alessia Sambri and Emiliano Di Gennaro and Jeppe B. Jacobsen and Henrik Jacobsen and Iulia Cojocariu and Marcin Szpytma and Andrea Locatelli and Tevfik Mentes and Matthieu Jamet and Jean-François Jacquot and Pasquale Orgiani and Ralph Ernstorfer and Ilija Zeljkovic and Younghun Hwang and Matteo Calandra and Jill A. Miwa and Federico Mazzola},
journal= {arXiv preprint arXiv:2502.20010},
year = {2026}
}