AUTHOR=Ghosh Sudeep Kumar , Li Bin , Xu Chunqiang , Hillier Adrian D. , Biswas Pabitra K. , Xu Xiaofeng , Shiroka Toni 

TITLE=ZrOsSi: a Z2 topological metal with a superconducting ground state

JOURNAL=Frontiers in Physics

VOLUME=11

YEAR=2023

URL=https://www.frontiersin.org/journals/physics/articles/10.3389/fphy.2023.1256166

DOI=10.3389/fphy.2023.1256166

ISSN=2296-424X

ABSTRACT=<p>The silicide superconductors (Ta, Nb, Zr)OsSi are among the best candidate materials for investigating the interplay of topological order and superconductivity. Here, we investigate in detail the normal-state topological properties of (Ta, Nb, Zr)OsSi, focusing on ZrOsSi, by employing a combination of <sup>29</sup>Si nuclear magnetic resonance (NMR) measurements and first-principles band-structure calculations. We show that, while (Ta, Nb)OsSi behave as almost ideal metals, characterized by weak electronic correlations and a relatively low density of states, the replacement of Ta (or Nb) with Zr expands the crystal lattice and shifts ZrOsSi towards an insulator. Our <italic>ab initio</italic> calculations indicate that ZrOsSi is a <italic>Z</italic><sub>2</sub> topological metal with clear surface Dirac cones and properties similar to a doped strong topological insulator.</p>