Seminars Archive

Time resolved XAS experiments at Elettra

Abstract
The x-ray absorption spectroscopy (XAS) is a widely used and well-established method for studying the electronic states and the local magnetic properties of matter at equilibrium. Adding the time-domain to XAS spectroscopy, the excited and transient states of complex systems become directly observable. As a whole, free electron lasers and synchrotron slicing sources are suitable for time-resolved experiments in time domains of tens of fs or less. Otherwise utilizing the time structure of the synchrotron sources, time-resolved XAS (TR-XAS) experiments are accessible with a time resolution which is limited by the length of the electron bunches, i.e., typically a few tens of ps. While most users exploit synchrotron radiation (SR) in multi-bunch filling mode as a very intense quasi-continuous light source, conventional laser-pump SR-probe experiments require the storage ring operating with dedicated filling modes, e.g., single-bunch, few-bunches, and hybrid modes. To overcome this limitation and to operate at variable repetition rates, the use of the multi-bunch filling pattern must be implemented with novel and effective acquisition concepts and ideas to perform time-resolved experiments in the sub-ns time domain. In this presentation, a synchronized femtolaser-pump SR-probe apparatus suitable for sub-nanosecond TR-XAS enhanced pump-probe experiments on conventional third generation storage rings, will be discussed. In addition, my recent research activity in this field will be presented and an outlook over the near future research will be given.