Attosecond transient absorption and four-wave mixing with tunable IR pulses

Nathan Harkema, The University of Arizona
Jens E. Bækhøj, Louisiana State University
Kenneth J. Schafer, Louisiana State University
Mette B. Gaarde, Louisiana State University
Chen Ting Liao, The University of Arizona
Arvinder Sandhu, The University of Arizona


We extend the technique of attosecond transient absorption spectroscopy by incorporating tunable IR pulses from an OPA. This technique is used to control Autler-Townes splitting and drive XUV four-wave mixing processes in Helium.