51st CEMS Colloquium


Dr. Xiuzhen Yu (Team Leader, Electronic States Microscopy Research Team, RIKEN CEMS)


17:30 - 18:30, June 28, 2017 (Wednesday)


Okochi-Hall, RIKEN


Realization and manipulation of topological spin textures


Skyrmion is a topological concept theoretically proposed more than half a century ago and has been confirmed recently in chiral-lattice helimagnets by small-angle neutron scattering and Lorentz transmission electron microscopy. A nanometric skyrmion consists of many electron-spins (from several to several hundreds) which subtend a solid angle of 4π, as characterized by a topological charge of unity. As spin-polarized electric current traverses the skyrmion, the conduction electrons sense the emergent field arising from the topological spin textures of skyrmion, and should be deflected. As a counteraction, skyrmion Hall motion appears owing to spin transfer torque effect. In this colloquium, I will show you how to realize and manipulate isolated skyrmions and skyrmion lattice with external stimuli in several systems by using advanced electron microscopy.