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arXiv · 1503.07893

Enhancing Magnetic Ordering in Cr-doped Bi2Se3 using High-TC Ferrimagnetic Insulator

Wenqing Liu·Liang He·Yongbing Xu·Koichi Murata·Mehmet C. Onbasli·Murong Lang·Nick J. Maltby·Shunpu Li·Xuefeng Wang·Caroline A. Ross·Peter Bencok·Gerrit van der Laan·Rong Zhang·Kang. L. Wang
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Abstract

We report a study of enhancing the magnetic ordering in a model magnetically doped topological insulator (TI), Bi2-xCrxSe3, via the proximity effect using a high-TC ferrimagnetic insulator Y3Fe5O12. The FMI provides the TI with a source of exchange interaction yet without removing the nontrivial surface state. By performing the elemental specific X-ray magnetic circular dichroism (XMCD) measurements, we have unequivocally observed an enhanced TC of 50 K in this magnetically doped TI/FMI heterostructure. We have also found a larger (6.6 nm at 30 K) but faster decreasing (by 80% from 30 K to 50 K) penetration depth compared to that of diluted ferromagnetic semiconductors (DMSs), which could indicate a novel mechanism for the interaction between FMIs and the nontrivial TIs surface.

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Wenqing Liu, Liang He, Yongbing Xu, Koichi Murata, Mehmet C. Onbasli, Murong Lang, Nick J. Maltby, Shunpu Li, Xuefeng Wang, Caroline A. Ross, Peter Bencok, Gerrit van der Laan, Rong Zhang, Kang. L. Wang. 2015-03-26. Enhancing Magnetic Ordering in Cr-doped Bi2Se3 using High-TC Ferrimagnetic Insulator. https://doi.org/10.1021/nl504480g

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