[printer friendly version]

AMO PHYSICS SEMINAR


"Probing exited-state electron dynamics with attosecond pulses"


Zenghu Chang
CREOL and Department of Physics
University of Central Florida


ABSTRACT 

Single isolated attosecond pulse is a new powerful tool for studying dynamics of correlated electron motion in pump-probe experiments. Such pulses, as short as 67 attoseconds, can now be generated with the Double Optical Gating method. The broadband XUV supercontinuum spectrum of the isolated attosecond pulse is particularly suitable for probing the time variation of the electronic states in transient absorption measurements. We performed the first measurement of AC Stack shift of the helium 1snp manifold of excited states using isolated attosecond pulses. With this measurement, we can fully characterize the energy shift of each excited state and observe dynamics of electrons in these states with unprecedented time resolution. The same method was also used to time-resolve the Fano profile which is the result of interference between the direct ionization and the decay from an autoionizing state due to configuration interaction.


Friday, December 7, 2012
IQSE 578, 2:00 p.m.
Mitchell Physics Building


Department of Physics and Astronomy
Texas A&M University

(Coffee and Cookies to be served 1:45 p.m.)