Study of magnetic domains by magnetic soft x-ray transmission microscopy*

X-ray magnetic circular dichroism serves as a strong element-specific magnetic contrast mechanism in full-field transmission soft x-ray microscopy to image micromagnetic domain structures. A lateral resolution down to 25 nm is provided by Fresnel zone plates used as optical elements. Recording the images in varying external magnetic fields and the sensitivity to the direction of the magnetization allows for detailed studies of static magnetization reversal processes in magnetic thin films and nanopatterned elements. Results on highly magnetostrictive Terfenol-D layers are reported. The experimental findings of the switching processes in soft magnetic permalloy rectangular structures are consistent with micromagnetic simulations. The pulsed time structure of polarized synchrotron radiation allows for a stroboscopic imaging of spin dynamics on a sub-nanosecond timescale.