Driving Rabi oscillations at the giant dipole resonance in xenon

TL;DR

This paper explores the feasibility of inducing Rabi oscillations in xenon atoms using intense free-electron laser pulses targeting the giant dipole resonance, revealing potential for controlled atomic dynamics at ultrafast timescales.

Contribution

It demonstrates the possibility of driving Rabi oscillations in xenon via FEL pulses exploiting the giant dipole resonance, with specific intensity and pulse duration requirements.

Findings

Rabi oscillations can be induced at around 10^18 W/cm^2.

Autler-Townes splittings appear in the photoelectron spectrum.

Optimal pulse duration is under 100 as to prevent full ionization.

Abstract

Free-electron lasers (FELs) produce short and very intense light pulses in the XUV and x-ray regimes. We investigate the possibility to drive Rabi oscillations in xenon with an intense FEL pulse by using the unusually large dipole strength of the giant-dipole resonance (GDR). The GDR decays within less than 30 as due to its position, which is above the $4d$ ionization threshold. We find that intensities around 10$^{18}$ W/cm$^2$ are required to induce Rabi oscillations with a period comparable to the lifetime. The pulse duration should not exceed 100 as because xenon will be fully ionized within a few lifetimes. Rabi oscillations reveal themselves also in the photoelectron spectrum in form of Autler-Townes splittings extending over several tens of electronvolt.