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arXiv · 1309.6754

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

S. Rößler·Tae-Hwan Jang·D. J. Kim·L. H. Tjeng·Z. Fisk·F. Steglich·S. Wirth
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Abstract

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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S. Rößler, Tae-Hwan Jang, D. J. Kim, L. H. Tjeng, Z. Fisk, F. Steglich, S. Wirth. 2013-09-26. Hybridization gap and Fano resonance in SmB${_6}$. https://doi.org/10.1073/pnas.1402643111

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