Veranstaltungsdetails

6.7.2006, 15:30
Jungiusstr. 11, Hörsaal AP

SFB 668 - Kolloquium

Dr. Dong-Hyun Kim (Center of X-ray Optics, Lawrence Berkeley National Lab, Berkeley CA, USA):

Magnetic Imaging with X-ray Microscopy : Spin Fluctuation, Vortex Dynamics, and Spin-Torque

Magnetic imaging techniques and visualization of magnetic domain and spin configuration have been providing fundamental insight in understanding magnetism as well as in realizing upcoming spintronic devices. Full-field transmission X-ray microscope (XM-1) developed at beamline 6.1.2 in Advanced Light Source synchrotron at Berkeley is very suitable tool that allows us to investigate spin dynamics and subsequent magnetic domain behavior with 15-nm spatial resolution and 70-ps temporal resolution. In this talk, several interesting experimental results achieved by means of XM-1 will be presented focusing on (1) nontrivial spin fluctuation and its statistical characteristics, (2) picosecond dynamics of magnetic vortex and interaction of multiple vortices in several ferromagnetic patterns investigated by electronic pump-probe stroboscopy, and (3) direct observation of domain wall motion in the ferromagnetic rings driven by the spin-torque exerted by nanosecond pulsed spin-polarized currents.