Topic: A study of artificial magnetic skyrmions
Speaker: Professor Ziqiang Qiu (邱子强 教授)
Department of Physics University of California at Berkeley
Time: 15:30 (Fri.) June 9th, 2017
Venue: Room 468，Lee Hsun Building, IMR CAS
Abstract
A magnetic skyrmion is a topological twist of two-dimensional spin texture which exhibits many fascinating properties. In experiment, magnetic skyrmions were recently realized in 2009 in several experimental systems as a result of Dzyaloshinsky-Moriya interactions (DMI). An alternative approach is to produce non-collinear spins in magnetic vortex states. With this motivation, we fabricated single crystalline Co disks on perpendicularly magnetized Ni/Cu(001) film to create artificial skyrmions whose topology can be tailored by changing the relative orientation between the vortex core polarity and the surrounding perpendicular magnetization. In this way, we studied the topological effect of the skyrmion using Photoemission Electron Microscopy (PEEM). By applying an in-plane magnetic field of various strengths, we find strong evidence that the annihilation of the vortex core depends on the topological skyrmion number of the system.
[1] 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, “Tailoring the topology of an artificial magnetic skyrmion”, Nature Communications 5, 4704 (2014).
[2] Kyoung-Woong Moon, Duck-Ho Kim, Soong-Geun Je, Byong Sun Chun, Wondong Kim, Z.Q. Qiu, Sug-Bong Choe, and Chanyong Hwang, “Skyrmion motions driven by oscillating under magnetic field oscillations”, Science Reports 5, 11055 (2015).
Biography
