Time-Resolved Soft X-ray Photoelectron Spectroscopy: Real-Time Observation of Photo-Excited Carriers at Semiconductor Surfaces

Abstract

Synchrotron radiation (SR) is a pulsed light source with a temporal width of about 50 picoseconds. Time-resolved soft X-ray photoelectron spectroscopy (PES), which combines SR soft X-ray with ultrashort pulse laser, allows to study the transient variation of electronic structures of materials with a time resolution of 50 picoseconds in a wide range of time scale from picoseconds to milliseconds. In this article, the time-resolved soft X-ray PES system developed at SPring-8 BL07LSU is described to explain the challenges and solutions in the time-resolved PES experiments. Study of carrier dynamics on oxide semiconductor surfaces is presented as one of the applications by time-resolved PES.