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Title: Magnetic and defect probes of the SmB 6 surface state
The impact of nonmagnetic and magnetic impurities on topological insulators is a central focus concerning their fundamental physics and possible spintronics and quantum computing applications. Combining scanning tunneling spectroscopy with transport measurements, we investigate, both locally and globally, the effect of nonmagnetic and magnetic substituents in SmB 6 , a predicted topological Kondo insulator. Around the so-introduced substitutents and in accord with theoretical predictions, the surface states are locally suppressed with different length scales depending on the substituent’s magnetic properties. For sufficiently high substituent concentrations, these states are globally destroyed. Similarly, using a magnetic tip in tunneling spectroscopy also resulted in largely suppressed surface states. Hence, a destruction of the surface states is always observed close to atoms with substantial magnetic moment. This points to the topological nature of the surface states in SmB 6 and illustrates how magnetic impurities destroy the surface states from microscopic to macroscopic length scales.  more » « less
Award ID(s):
1708199
PAR ID:
10093171
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Science Advances
Volume:
4
Issue:
11
ISSN:
2375-2548
Page Range / eLocation ID:
eaau4886
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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