title: Enhancing magnetic ordering in Cr-doped Bi2Se3 using high-TC ferrimagnetic insulator.
abstract: We report a study of enhancing the magnetic ordering in a model magnetically doped topological insulator (TI), Bi(2-x)Cr(x)Se(3), via the proximity effect using a high-TC ferrimagnetic insulator Y(3)Fe(5)O(12). 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 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.
authors.affiliation: York-Nanjing Joint Center for Spintronics and Nano Engineering (YNJC), School of Electronics Science and Engineering, Nanjing University , Nanjing 210093, China.
authors.forename: Wenqing
authors.initials: W
authors.lastname: Liu
authors.forename: Liang
authors.initials: L
authors.lastname: He
authors.forename: Yongbing
authors.initials: Y
authors.lastname: Xu
authors.forename: Koichi
authors.initials: K
authors.lastname: Murata
authors.forename: Mehmet C
authors.initials: MC
authors.lastname: Onbasli
authors.forename: Murong
authors.initials: M
authors.lastname: Lang
authors.forename: Nick J
authors.initials: NJ
authors.lastname: Maltby
authors.forename: Shunpu
authors.initials: S
authors.lastname: Li
authors.forename: Xuefeng
authors.initials: X
authors.lastname: Wang
authors.forename: Caroline A
authors.initials: CA
authors.lastname: Ross
authors.forename: Peter
authors.initials: P
authors.lastname: Bencok
authors.forename: Gerrit
authors.initials: G
authors.lastname: van der Laan
authors.forename: Rong
authors.initials: R
authors.lastname: Zhang
authors.forename: Kang L
authors.initials: KL
authors.lastname: Wang
mesh_terms: D001729:Bismuth; D002857:Chromium; D059346:Magnets; D012643:Selenium; D012666:Semiconductors
chemical_list: D002857:Chromium; D012643:Selenium; D001729:Bismuth
keywords: Magnetic topological insulator; XMCD; ferrimagnetic insulator YIG; proximity effect; spintronics