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arXiv · 2003.03224

Comparative Scanning Tunneling Microscopy Study on Hexaborides

S. Wirth·Sahana Rößler·Lin Jiao·M. Victoria Ale Crivillero·Priscila F. S. Rosa·Z. Fisk
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Abstract

We compare STM investigations on two hexaboride compounds, SmB$_6$ and EuB$_6$, in an effort to provide a comprehensive picture of their surface structural properties. The latter is of particular importance for studying the nature of the surface states in SmB$_6$ by surface-sensitive tools. Beyond the often encountered atomically rough surface topographies of {\it in situ}, low-temperature cleaved samples, differently reconstructed as well as B-terminated and, more rarely, rare-earth terminated areas could be found. With all the different surface topographies observed on both hexaborides, a reliable assignment of the surface terminations can be brought forward.

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S. Wirth, Sahana Rößler, Lin Jiao, M. Victoria Ale Crivillero, Priscila F. S. Rosa, Z. Fisk. 2020-03-06. Comparative Scanning Tunneling Microscopy Study on Hexaborides. https://doi.org/10.1002/pssb.202000022

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