Magnetic imaging with femtosecond temporal resolution.
A scanning Kerr microscope with a temporal resolution of <230 fs and a spatial resolution of 210 nm is presented. Equipped with a large temporal and spatial scanning range of 8 ns and 320 microm, respectively, the microscope allows studying nonuniform magnetization dynamics on many different time scales over a large area. For demonstration, we study the magnetization dynamics in Fe/Gd multilayer dot arrays exhibiting a spin reorientation transition (SRT) on three different time scales, namely, femtosecond, picosecond, and nanosecond scales. The dynamics on all time scales varies from one dot to another. This is attributed to the high sensitivity of the SRT to the variations of the layer thicknesses and the Fe/Gd interface structure.
Li
Jie
J
Junior Research Group Magnetic Microscopy, Institute for Experimental Physics IV, Ruhr-University of Bochum, Universitätsstr. 150, D-44780 Bochum, Germany.
Lee
Min-Sang
MS
He
Wei
W
Redeker
Björn
B
Remhof
Arndt
A
Amaladass
Edward
E
Hassel
Christoph
C
Eimüller
Thomas
T