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arXiv · 2403.04550

Electrical transport signatures of metallic surface state formation in the strongly-correlated insulator FeSb2

Alexander G. Eaton·Nicholas J. M. Popiel·Ke-Jun Xu·Alexander J. Hickey·Hsu Liu·Monica Ciomaga Hatnean·Geetha Balakrishnan·Gunnar F. Lange·Robert-Jan Slager·Zhi-Xun Shen·Suchitra E. Sebastian
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Abstract

We present local and nonlocal electrical transport measurements of the correlated insulator FeSb$_2$. By employing wiring configurations that delineate between bulk- and surface-dominated conduction, we reveal the formation of a metallic surface state in FeSb$_2$ for temperatures $\lessapprox 5$~K. This result is corroborated by an angular rotation study of this material's magnetotransport, which also shows signatures of the transition from bulk- to surface-dominated conduction over the same temperature interval as the local/nonlocal transport divergence. Notable similarities with the topological Kondo insulator candidate SmB$_6$ are discussed.

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Alexander G. Eaton, Nicholas J. M. Popiel, Ke-Jun Xu, Alexander J. Hickey, Hsu Liu, Monica Ciomaga Hatnean, Geetha Balakrishnan, Gunnar F. Lange, Robert-Jan Slager, Zhi-Xun Shen, Suchitra E. Sebastian. 2024-03-07. Electrical transport signatures of metallic surface state formation in the strongly-correlated insulator FeSb2. https://arxiv.org/abs/2403.04550

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