Speaker:
Zhiqiang Qiu
Institution:
UC Berkeley
Date:
Wednesday, March 11, 2015
Time:
4:00 pm
Location:
NS2 1201
ABSTRACT:
A magnetic Skyrmion is a topological twist of 2D spin textures 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 strength, we find strong evidence that the annihilation of the vortex core depends on the Skyrmion number of the system.
Host:
Jing Xia