Laser-driven switching dynamics in phase change materials investigated by time-resolved X-ray absorption spectroscopy

Time-dependent X-ray absorption spectroscopy at the Ge L-3 edge is used to study the optical switching dynamics of epitaxial phase change materials grown on Si(111) membranes. Small differences between the static absorption spectra of the crystalline and laser-amorphized phase of GeTe are observed. Furthermore, a new approach for pump-probe studies on phase change materials is presented. However, no time-dependent change in the X-ray absorption > 0.1% has been detected so far. This is mainly attributed to sample deterioration at 3 kHz pump-probe rates.