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Hybridization gap and Fano resonance in SmB${_6}$

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 نشر من قبل Steffen Wirth
 تاريخ النشر 2013
  مجال البحث فيزياء
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We present results of Scanning Tunneling Microscopy and Spectroscopy (STS) measurements on the Kondo insulator SmB$_6$. The vast majority of surface areas investigated was reconstructed but, infrequently, also patches of varying size of non-reconstructed, Sm- or B-terminated surfaces were found. On the smallest patches, clear indications for the hybridization gap and inter-multiplet transitions were observed. On non-reconstructed surface areas large enough for coherent co-tunneling we were able to observe clear-cut Fano resonances. Our locally resolved STS indicated considerable finite conductance on all surfaces independent of their structure.



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