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德国马普固体化物所郭汉杰博士学术报告通知

【来源:物理学院 | 发布日期:2017-12-27 | 作者:null 】     【选择字号:
    应物理科学与技术学院李志伟副教授邀请,德国马普学会固体化物所郭汉杰博士来我院访问并做学术报告,欢迎大家参加。
    报告信息如下:
    时间:2018年1月5日(星期五五)上午10:00
    地点:格致楼3016学术报告厅
    报告人:郭汉杰,主要从事凝聚态物理领域相关的研究工作,是晶体生长、晶体结构及XRD精修,磁结构分析、中子/X-射线散射及uSR等领域的专家。
    报告题目:Magnetic Ground State of the Pyrochlore Iridate
 
    摘要:

     Pyrochlore iridates (R2Ir2O7, R = Y and rare earth elements) are of great interest due to the interplay between the relatively large spin-orbit coupling and the electron-electron correlations which may induce novel phases such as topological Mott insulators, axion insulators and Weyl semimetals. One important task for understanding the properties of these compounds is the determination of the magnetic structure which is challenging due to the small moment of the Ir4+ ions and strong neutron absorption from Ir atoms. In this talk, I will present our studies on the magnetic ground state of Nd2Ir2O7 and Tb2Ir2O7 by means of muon spin relaxation and powder neutron diffraction technique [1-3]. Our studies determine the magnetic structure directly, which can be described as the so-called all-in/all-out structure. The comparison between the Nd2Ir2O7 and Tb2Ir2O7 results also shows that the Ir4+ moment is larger with higher TN (smaller R-ionic radius as well), suggesting that the hybridization between the Ir 5d and O 2p orbitals is smaller with decreasing R-ionic radius.

 References:

[1] H. Guo, K. Matsuhira, I. Kawasaki, M. Wakeshima, Y. Hinatsu, I. Watanabe, and Z. Xu, Phys. Rev. B, 88, 060411 (R) (2013).

[2] H. Guo, C. Ritter and A. C. Komarek, Phys. Rev. B 94, 161102(R) (2016).

[3] H. Guo, C. Ritter and A. C. Komarek, Phys. Rev. B 96, 144415 (2017)

报告人简介:
2014/09 - now: Scientist at Max-Planck-Institute for Chemical Physics of Solids, Dresden Germany
2009/09 - 2014/06: PhD, Department of Physics, Zhejiang University, China
2012/02 - 2013/12: International Program Associate student in RIKEN, Japan
2005/09 - 2009/06: B.S., Department of Mechanical Engineering and Automation, Huaqiao University, China.