Open AccessMagnetoresistance Anomaly in Topological Kondo Insulator SmB 6 Nanowires with Strong Surface Magnetism
Author(s) -
He Xingshuai,
Gan Haibo,
Du Zongzheng,
Ye Bicong,
Zhou Liang,
Tian Yuan,
Deng Shaozhi,
Guo Guoping,
Lu Haizhou,
Liu Fei,
He Hongtao
Publication year - 2018
Publication title -
advanced science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.388
H-Index - 100
ISSN - 2198-3844
DOI - 10.1002/advs.201700753
Subject(s) - kondo insulator , magnetoresistance , condensed matter physics , magnetism , topological insulator , nanowire , surface states , kondo effect , topology (electrical circuits) , materials science , electron , anomaly (physics) , physics , surface (topology) , magnetic field , nanotechnology , quantum mechanics , geometry , mathematics , combinatorics
Topological Kondo insulators (TKIs) are a new class of topological materials in which topological surface states dominate the transport properties at low temperatures. They are also an ideal platform for studying the interplay between strong electron correlations and topological order. Here, hysteretic magnetoresistance (MR) is observed in TKI SmB 6 thin nanowires at temperatures up to 8 K, revealing the strong magnetism at the surface of SmB 6 . It is also found that such MR anomaly exhibits an intriguing finite size effect and only appears in nanowires with diameter smaller than 58 nm. These nontrivial phenomena are discussed in terms of the latest Kondo breakdown model, which incorporates the RKKY magnetic interaction mediated by surface states with the strong electron correlation in SmB 6 . It would provide new insight into the nature of TKI surface states. Additionally, a non‐monotonically temperature dependent positive magnetoresistance is observed at intermediate temperatures, suggesting the possible impurity‐band conduction in SmB 6 , other than the surface state transport at low temperatures and the bulk‐band transport at high temperatures.