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arXiv · 2607.26804

Disentangling bulk and surface states in the electronic structure of PtBi$_2$(0001)

Stefanie Suzanne Brinkman·Xin Liang Tan·Anders Christian Mathisen·Fabian Göhler·Øyvind Finnseth·Chul-Hee Min·Grigory Shipunov·Falk Pabst·Manuel Alonso Lemos·Balasubramanian Thiagarajan·Craig Polley·Masashi Arita·Kenya Shimada·Anna Isaeva·Jorge I. Facio·Hendrik Bentmann
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Abstract

Recent reports of surface-localized topological superconductivity in trigonal PtBi$_2$ highlight the importance of understanding its surface electronic structure. We investigate the bulk and surface band structure of PtBi$_2$ using angle-resolved photoemission spectroscopy (ARPES) and first-principles calculations. Through photon-energy- and polarization-dependent measurements, we disentangle bulk dispersions from surface states on the two distinct surface terminations of PtBi$_2$(0001). For both terminations, we assign several different surface states and find good agreement between experiment and calculations. Based on our calculations, we analyze the orbital composition in the surface and bulk bands and compare the results to polarization-dependent ARPES measurements. Together, our results provide a coherent picture of the surface electronic structure of PtBi$_2$ across both surface terminations.

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Stefanie Suzanne Brinkman, Xin Liang Tan, Anders Christian Mathisen, Fabian Göhler, Øyvind Finnseth, Chul-Hee Min, Grigory Shipunov, Falk Pabst, Manuel Alonso Lemos, Balasubramanian Thiagarajan, Craig Polley, Masashi Arita, Kenya Shimada, Anna Isaeva, Jorge I. Facio, Hendrik Bentmann. 2026-07-29. Disentangling bulk and surface states in the electronic structure of PtBi$_2$(0001). https://arxiv.org/abs/2607.26804

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