报告人：栗佳  研究员

北京大学物理学院、量子材料科学中心

邀请人：颜世申 教授

报告时间：2017年3月3日 下午 3:30

报告地点：知新楼C1111

摘要:

尽管已经研究多年，目前绝大部分针对自旋流的实验测量都是间接的测量。我们利用相位耦合技术，将同步辐射 X 光和微波磁场同步耦合，搭建了 X-射线铁磁共振技术，并且利用这一技术研究了 Py/Cu/Cu75Mn25/Cu/Co 多层膜中的自旋泵浦。 在实验中我们利用 Py 层的铁磁共振将交流自旋流注入 Cu75Mn25和 Co 层，并且成功在 Cu75Mn25 和 Co 层中直接测量到了交流自旋流。利用这一元素分辨与时间分辨的实验技术，我们在实验中明白无误地确认了交流自旋流。

报告人介绍：

栗佳，研究员， 北京大学物理学院量子材料科学中心

教育背景

 2005 年-2010 年，复旦大学物理系，博士

 2001 年-2005 年，复旦大学材料科学系，学士

工作经历

 2016 年-   北京大学量子材料科学中心，研究员

  2010 年-2015 年， 加州大学伯克利分校物理系，博士后

 2007 年 11 月-2007 年 12 月和 2008 年 5 月-2008 年 8 月， 德国马克斯普朗克微结构研究所，访问学生

研究方向

1. 人工磁性纳米结构的拓扑磁性和拓扑操控。

2. 磁性氧化物薄膜的磁结构及自旋阻挫。

3. 各类磁性材料的超快磁性研究。

4. 微波频率下的自旋电子学研究，重点研究自旋电流的物理性质。

代表性论文

1. Spin-current probe for phase transition in an insulator   Zhiyong Qiu, Jia Li, Dazhi Hou, Elke Arenholz, Alpha T. N’Diaye , Ali Tan, Ken-ichi Uchida, Koji Sato, Satoshi Okamoto, Yaroslav Tserkovnyak, Z.Q. Qiu and Eiji Saitoh  Nature Communications 7, 12670 (2016)

2. Direct detection of pure ac spin current by x-ray pump-probe measurements  J. Li, L. R. Shelford, P. Shafer, A. Tan, J. X. Deng, P. S. Keatley, C. Hwang, E. Arenholz, G. van der Laan, R. J. Hicken, and Z. Q. Qiu  Phys. Rev. Lett. 117, 076602 (2016)

 3. Topology of spin meron pairs in coupled Ni/Fe/Co/Cu(001) disks  A. Tan, J. Li*, A. Scholl, E. Arenholz, A. T. Young, Q. Li, C. Hwang, and Z. Q. Qiu  Phys. Rev. B 94, 014433 (2016)

 4. In-plane spin reorientation transition in Co/Py bilayers grown epitaxially on vicinal Cu(001)  J. X. Deng, A. Tan, J. Li, C. Hwang, and Z. Q. Qiu  J. Magn. Magn. Mater. 408, 193 (2016)

 5. Tailoring the magnetic anisotropy of Py/Ni bilayer films using well aligned atomic steps on Cu(001)  S. Ma, A. Tan, J. X. Deng, J. Li, Z. D. Zhang, C. Hwang, and Z. Q. Qiu  Scientific Reports 5, 11055 (2015)

 6. Extending resonant inelastic X-ray scattering to the extreme ultraviolet  L. Andrew Wray, Shih-Wen Huang, Ignace Jarrige, Kazuhiko Ikeuchi, Kenji Ishii, Jia Li, Z. Q. Qiu, Zahid Hussain, Yi-De Chuang  Frontiers in Physics (section Condensed Matter Physics) 10, 3389 (2015)

 7. Chirality switching and winding/unwinding of the antiferromagnetic NiO domain walls in Fe/NiO/Fe/CoO/Ag(001)  J. Li, A. Tan, S. Ma, R. F. Yang, E. Arenholz, C. Hwang, and Z. Q. Qiu  Phys. Rev. Lett. 113, 147207 (2014)

 8. Tailoring the topology of an artificial magnetic skyrmion  J. Li, A. Tan, K. W. Moon, A. Doran, M. A. Marcus, A. T. Young, E. Arenholz, S. Ma, R. F. Yang, C. Hwang, and Z. Q. Qiu  Nature Communications 5, 4704 (2014)

 9. Stabilizing a magnetic vortex/antivortex array in single crystalline Fe/Ag(001) microstructures  J. Li, A. Tan, K. W. Moon, A. Doran, M. A. Marcus, A. T. Young, E. Arenholz, S. Ma, R. F. Yang, C. Hwang, and Z. Q. Qiu  Appl. Phys. Lett. 104, 262409 (2014)

 10. Imprinting antivortex states from ferromagnetic Fe into antiferromagnetic NiO in epitaxial NiO/Fe/Ag(001) microstructures  J. Li, A. Tan, K. W. Moon, A. Doran, M. A. Marcus, A. T. Young, E. Arenholz, S. Ma, R. F. Yang, C. Hwang, and Z. Q. Qiu  Appl. Phys. Lett. 104, 112407 (2014)

 11. Novel Chiral Magnetic DomainWall Structure in Fe/Ni/Cu(001) Films  G. Chen, J. Zhu, A. Quesada, J. Li, A. T. N'Diaye, Y. Huo, T.P. Ma, Y. Chen, H.Y. Kwon, C. Won, Z.Q. Qiu, A.K. Schmid, and Y. Z. Wu  Phys. Rev. Lett. 110, 177204 (2013)

12. Magnetic anisotropy in epitaxial Py/FeMn/Cu(001) and Py/FeMn/Ni/Cu(001) films  A. Tan, J. Li, C. A. Jenkins, E. Arenholz, A. Scholl, C. Hwang, and Z. Q. Qiu  Phys. Rev. B 88, 104404 (2013)

 13. Measurement of the spectral line shapes for orbital excitations in the Mott insulator CoO using high-resolution resonant inelastic x-ray scattering  L. Andrew Wray, J. Li, Z. Q. Qiu, Jinsheng Wen, Zhijun Xu, GendaGu, ShihWen Huang, Elke Arenholz, Wanli Yang, Zahid Hussain, and Yi-De Chuang  Phys. Rev. B 88, 035105 (2013)

 14. Magnetic dead layer at the interface between a Co film and the topological insulator Bi2Se3  J. Li, Z. Y. Wang, A. Tan, P.-A. Glans, E. Arenholz, C. Hwang, J. Shi, and Z. Q.Qiu  Phys. Rev. B 86, 054430 (2012)

 15. Design of a vector magnet for the measurements of anisotropic magnetoresistance and rotational magneto-optic Kerr effect  J. Li, E. Jin, H. Son, A. Tan, W. N. Cao, Chanyong Hwang, and Z. Q. Qiu  Review of Scientific Instruments 83, 033906 (2012)

 16. Exchange bias in epitaxially grown CoO/MgO/Fe/Ag(001)  A. Tan, J. Li, C. A. Jenkins, E. Arenholz, A. Scholl, C. Hwang, and Z. Q. Qiu  Phys. Rev. B 86, 064406 (2012)

 17. Magnetic interlayer coupling between antiferromagnetic CoO and ferromagnetic Fe across a Ag spacer layer in epitaxially grown CoO/Ag/Fe/Ag(001)  Y. Meng, J. Li, P.-A. Glans, C. A. Jenkins, E. Arenholz, A. Tan, J. Gibbons, J. S. Park, Chanyong Hwang, H. W. Zhao, and Z. Q. Qiu  Phys. Rev. B 85, 014425 (2012)

 18. NiO-thickness dependent magnetic anisotropies in Fe/NiO/Au(001) and Fe/NiO/MgO(001) systems  L.Y. Ma, G. Chen, J. Li, J. Zhu, Z.Q.Qiu and Y.Z. Wu  J. Magn. Magn.Mater. 324, 528 (2012)

 19. Determination of the Fe magnetic anisotropies and the CoO frozen spins in epitaxial CoO/Fe/Ag(001)  J. Li, Y. Meng, J. S. Park, C.A. Jenkins, E. Arenholz, A. Scholl, A. Tan, H. Son, H. W. Zhao, Chanyong Hwang, Y. Z. Wu, and Z. Q. Qiu  Phys. Rev. B 84, 094447 (2011)

20. Continuous Spin Reorientation Transition in Epitaxial Antiferromagnetic NiO Thin Films  J. Li, E. Arenholz, Y. Meng, A. Tan, J. Park, E. Jin, H. Son, J. Wu, C.A. Jenkins, A. Scholl, H. W. Zhao, Chanyong Hwang, and Z. Q. Qiu  Phys. Rev. B 84, 012406 (2011)

 21. In-plane spin reorientation transition in Fe/NiO bilayers on Ag(1,1,10)  J. Li, M. Przybylski, F. Yildiz, X.L. Fu, and Y. Z. Wu  Phys. Rev. B 83, 094436 (2011)

 22. Quantum Well States and Oscillatory Magnetic Anisotropy in Ultrathin Fe Films  J. Li, G. Chen, M. Przybylski, E. Rotenberg, and Y. Z. Wu  IEEE Tran. Magn. 47, 1603 (2011)

 23. A study of FeMn/Fe/Co/Cu(1,1,10) films using MOKE and XMCD  Y. Meng, J. Li, A. Tan, J. Park, E. Jin, H. Son, A. Doran, A. Scholl, E. Arenholz, H. W. Zhao, Chanyong Hwang, and Z. Q. Qiu  Phys. Rev. B 84, 064416 (2011)

 24. Element-specific study of epitaxial NiO/Ag/CoO/Fe films grown on vicinal Ag(001) using Photoemission Electron Microscopy  Y. Meng, J. Li, A. Tan, E. Jin, J. Son, J. S. Park, A. Doran, A.T. Young, A. Scholl, E. Arenholz, J. Wu, C. Hwang, H. W. Zhao, and Z. Q. Qiu  Appl. Phys. Lett. 98, 212508 (2011)

 25. Determination of spin-polarized quantum well states and spin-split energy dispersions of Co ultrathin films grown on Mo(110)  J. S. Park, A. Quesada, Y. Meng, J. Li, E. Jin, H. Son, A. Tan, J. Wu, C. Hwang, H. W. Zhao, A. K. Schmid, and Z. Q. Qiu  Phys. Rev. B 83, 113405 (2011)

 26. Temperature-dependent magnetic anisotropies in epitaxial Fe/CoO/MgO(001) system studied by the planar Hall effect

 W. N. Cao, J. Li, G. Chen, J. Zhu, C.R. Hu, and Y. Z. Wu  Appl. Phys. Lett. 98, 262506 (2011)

 27. Revealing the volume magnetic anisotropy of Fe films epitaxied on GaAs(001) surface  G. Chen, J. Zhu, J. Li, F. Z. Liu, and Y. Z. Wu  Appl. Phys. Lett. 98, 132505 (2011)

 28. Experimental observation of quantum oscillations of perpendicular anisotropy in Fe films on Ag(1,1,10)  J. Li,M. Przybylski, Y. He, and Y. Z. Wu  Phys. Rev. B 82, 214406 (2010)

 29. Four-fold magnetic anisotropy induced by the antiferromagnetic order in FeMn/Co/Cu(001) system  G. Chen, J. Li, F. Z. Liu, J. Zhu, Y. He, J. Wu, Z. Q. Qiu, and Y. Z. Wu  J. Appl. Phys. 108, 073905 (2010)

 30. Oscillatory Magnetic Anisotropy Originating from Quantum Well States in Fe Films  J. Li, M. Przybylski, F. Yildiz, X. D. Ma, and Y. Z. Wu  Phys. Rev. Lett. 102, 207206 (2009)