Discovering and engineering spin-polarised surface states in the electronic structures of condensed matter systems is a crucial first step in development of spintronic devices, wherein spin-polarised bands crossing the Fermi level can facilitate information transfer. Here, we show how the spin-orbit split K-point valleys of monolayer WSe2 can be made potentially suitable for this purpose, despite the semiconducting ground state. By interfacing with metallic 2H-NbSe2, these valence band extrema are shifted by ∼800~meV to produce a surface-localised Fermi surface populated only by spin-polarised carriers. By increasing the WSe2 thickness, the Fermi pockets can be moved from K to Γ, demonstrating tunability of novel semi-metallic phases that exist atop a substrate additionally possessing charge density wave and superconducting transitions. Together, this study provides spectroscopic understanding into p-type, Schottky barrier-free interfaces, which are of urgent interest for bypassing the limitations of current-generation vertical field effect transistors, in addition to longer-term spintronics development.
@article{arxiv.2509.14937,
title = {Spin-polarised surface fermiology of ohmic WSe$_2$/NbSe$_2$ interfaces},
author = {Oliver J. Clark and Thi-Hai-Yen Vu and Ben A. Chambers and Federico Mazzola and Sadhana Sridhar and Geetha Balakrishnan and Aaron Bostwick and Chris Jozwiak and Eli Rotenberg and Sarah L. Harmer and Michael S. Fuhrer and Mark T. Edmonds},
journal= {arXiv preprint arXiv:2509.14937},
year = {2025}
}