Sub-20-fs Optical Pump-X-ray Probe Spectroscopy beyond the Si K Edge

Abstract

Time resolved x-ray absorption spectroscopy is a powerful tool to follow the fast atomic, molecular changes on the atomic time and spatial scale. Here we demonstrate timeresolved XANES and EXAFS relying on a laser driven ultrafast XUV source. We have examined the electronic and structural changes in amorphous Si with a temporal resolution of 20 fs.