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Comparative Scanning Tunneling Microscopy Study on Hexaborides

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 نشر من قبل Steffen Wirth
 تاريخ النشر 2020
  مجال البحث فيزياء
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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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