Intrinsic topological superconductors with protected boundary modes obeying non-Abelian statistics constitute a vanishingly small class of quantum materials. A defining spectroscopic signature of such phases is the presence of in-gap topological surface states (TSS). However, despite extensive theoretical proposals, their unambiguous experimental identification has remained elusive. Here we use vector magnetic-field scanning tunnelling microscopy to obtain direct spectroscopic evidence of TSS in the spin-triplet superconductor UTe2. Atomic-scale spectroscopy reveals striking site-dependent superconductivity: Te sites host a large in-gap density of states that nearly fills the superconducting gap, whereas neighboring atomic sites remain gapped. Upon application of a magnetic field, the in-gap states on the Te sites are selectively suppressed, yielding a spatially homogeneous superconducting state with a markedly deeper gap relative to zero field. This site-selective gap evolution is in quantitative agreement with theoretical predictions for TSS in UTe2 that possess dominant Te-orbital character. Spectral-function calculations incorporating the Zeeman coupling reproduce the observed magnetic-field response. Our results provide a spectroscopic fingerprint of the long-sought TSS in superconductors and establish UTe2 as a compelling system for exploring intrinsic topological superconductivity.
@article{arxiv.2604.04883,
title = {Topological surface states revealed by the Zeeman effect in superconducting UTe2},
author = {Zhen Zhu and Hans Christiansen and Yudi Huang and Kaiming Liu and Zheyu Wu and Shanta R. Saha and Johnpierre Paglione and Alexander G. Eaton and Andrej Cabala and Michal Vališka and Rafael M. Fernandes and Andreas Kreisel and Brian M. Andersen and Vidya Madhavan},
journal= {arXiv preprint arXiv:2604.04883},
year = {2026}
}