@article{1c88f8343c984cdb8a6755ebe1e4a179,
title = "Above 400-K robust perpendicular ferromagnetic phase in a topological insulator",
abstract = "The quantum anomalous Hall effect (QAHE) that emerges under broken time-reversal symmetry in topological insulators (TIs) exhibits many fascinating physical properties for potential applications in nanoelectronics and spintronics. However, in transition metal–doped TIs, the only experimentally demonstrated QAHE system to date, the QAHE is lost at practically relevant temperatures. This constraint is imposed by the relatively low Curie temperature (Tc) and inherent spin disorder associated with the random magnetic dopants. We demonstrate drastically enhanced Tc by exchange coupling TIs to Tm3Fe5O12, a high-Tc magnetic insulator with perpendicular magnetic anisotropy. Signatures showing that the TI surface states acquire robust ferromagnetism are revealed by distinct squared anomalous Hall hysteresis loops at 400 K. Point-contact Andreev reflection spectroscopy confirms that the TI surface is spin-polarized. The greatly enhanced Tc, absence of spin disorder, and perpendicular anisotropy are all essential to the occurrence of the QAHE at high temperatures.",
author = "Chi Tang and Chang, {Cui Zu} and Gejian Zhao and Yawen Liu and Zilong Jiang and Liu, {Chao Xing} and Martha McCartney and David Smith and Tingyong Chen and Moodera, {Jagadeesh S.} and Jing Shi",
note = "Funding Information: We thank D. Yan, J. Li, Z. Shi, and N. Samarth for their help with experiments and discussions. Funding: The work at University of California, Riverside and Arizona State University (ASU) was supported as part of the SHINES (Spins and Heat in Nanoscale Electronic Systems), an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences under award no. SC0012670. C.-Z.C. and J.S.M. acknowledge the support from NSF grant no. DMR-1207469, Office of Naval Research (ONR) grant no. N00014-13-1-0301, and the Science and Technology Center for Integrated Quantum Materials under NSF grant no. DMR-1231319. C.-X.L. acknowledges the support from ONR grant no. N00014-15-1-2675. M.R.M. and D.J.S. acknowledge use of facilities at the John M. Cowley Center for High Resolution Electron Microscopy at ASU. Publisher Copyright: Copyright {\textcopyright} 2017 The Authors, some rights reserved.",
year = "2017",
month = jun,
doi = "10.1126/sciadv.1700307",
language = "English (US)",
volume = "3",
journal = "Science advances",
issn = "2375-2548",
publisher = "American Association for the Advancement of Science",
number = "6",
}