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arXiv · 1712.04184

Fermiology and Superconductivity of Topological Surface States in PdTe$_2$

O. J. Clark·M. J. Neat·K. Okawa·L. Bawden·I. Marković·F. Mazzola·J. Feng·V. Sunko·J. M. Riley·W. Meevasana·J. Fujii·I. Vobornik·T. K. Kim·M. Hoesch·T. Sasagawa·P. Wahl·M. S. Bahramy·P. D. C. King
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Abstract

We study the low-energy surface electronic structure of the transition-metal dichalcogenide superconductor PdTe$_2$ by spin- and angle-resolved photoemission, scanning tunneling microscopy, and density-functional theory-based supercell calculations. Comparing PdTe$_2$ with its sister compound PtSe$_2$, we demonstrate how enhanced inter-layer hopping in the Te-based material drives a band inversion within the anti-bonding p-orbital manifold well above the Fermi level. We show how this mediates spin-polarised topological surface states which form rich multi-valley Fermi surfaces with complex spin textures. Scanning tunneling spectroscopy reveals type-II superconductivity at the surface, and moreover shows no evidence for an unconventional component of its superconducting order parameter, despite the presence of topological surface states.

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O. J. Clark, M. J. Neat, K. Okawa, L. Bawden, I. Marković, F. Mazzola, J. Feng, V. Sunko, J. M. Riley, W. Meevasana, J. Fujii, I. Vobornik, T. K. Kim, M. Hoesch, T. Sasagawa, P. Wahl, M. S. Bahramy, P. D. C. King. 2017-12-12. Fermiology and Superconductivity of Topological Surface States in PdTe$_2$. https://doi.org/10.1103/physrevlett.120.156401

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