Speaker
Prof.
Ying Tsui
(University of Alberta)
Description
Warm Dense Matter (WDM) is a material under extreme conditions which has near solid density but has a temperature of several electron volts. It is a state lies in between condense matter state and plasma state. The study of materials under extreme conditions is currently a forefront area of study in material science and has generated enormous scientific interest. The understanding of WDM is important for laser material processing, which has many scientific and industrial applications, as well as Inertial Fusion Energy, which is a safe energy source that has no carbon emission and almost unlimited fuel supply. The understanding of WDM is also important for planetary science and astrophysics. Ultrafast pump-probe methods can been used to study the evolution of WDM in sub-picosecond time scale. When a high intensity ultrashort laser pulse is absorbed by a solid target, a non-equilibrium WDM with electron temperature of several electron volts, ion temperature near room temperature and density remains as solid is formed initially in less than a picosecond. During the subsequent several picoseconds the electron temperature reduces and ion temperature rises and target eventually disassembles into an expanding plasma. Ultrafast probing techniques based on optical, electron diffraction and x-ray diffraction have been used to study the properties of laser produced WDM led to a better understanding of WDM. An overview of our current understanding of laser produced WDM will be presented in this talk.
Author
Prof.
Ying Tsui
(University of Alberta)
