Second-harmonic generation of a short XUV pulse interacting with an IR-laser-dressed atom

The nonlinear response of an atomic system interacting with short extreme ultraviolet (XUV) and infrared (IR) pulses is considered within the adiabatic approach (for an IR field) and the perturbation theory (for an XUV pulse). The second-order perturbation theory in the XUV field is developed for the IR-dressed atom, and the laser-induced generation of a pulse with a doubled carrier XUV frequency is analyzed. We study the yield of harmonics in the frequency band of the generated doubled frequency XUV pulse as a function of the time delay between initial XUV and IR pulses. Our analytical and numerical results show that this dependence carries the time dependence of the intense IR pulse and can be utilized to retrieve the waveform of the IR pulse.

Automated summary

This article considers the nonlinear response of an atomic system interacting with XUV and IR pulses. The adiabatic approach and perturbation theory are used for the IR and XUV pulses respectively. The study analyzes the generation of a doubled carrier XUV frequency pulse induced by a laser and examines the yield of harmonics in the frequency band of the generated pulse based on the time delay between the initial XUV and IR pulses.