Autoionizing Polaritons in Attosecond Atomic Ionization

Abstract

Light-induced states are commonly observed in the photoionization spectra of laser-dressed atoms. The properties of autoionizing polaritons, entangled states of light and Auger resonances, however, are largely unexplored. We employ attosecond transient-absorption spectroscopy to study the evolution of autoionizing states in argon, dressed by a tunable femtosecond laser pulse. The avoided crossings between the $3s^{-1}4p$ and several light-induced states indicates the formation of polariton multiplets. We measure a controllable stabilization of the polaritons against ionization, in excellent agreement with \emph{ab initio} theory. Using an extension of the Jaynes-Cummings model to autoionizing states, we show that this stabilization is due to the destructive interference between the Auger decay and the radiative ionization of the polaritonic components. These results give new insights into the optical control of electronic structure in the continuum, and unlock the door to applications of autoionizing polaritons in poly-electronic systems.

5 pages, 3 figures

References in corpus (5)

• Coherent control with a short-wavelength Free Electron Laser
• Attosecond Control of Ionization Dynamics
• Femtosecond induced transparency and absorption in the extreme ultraviolet by coherent coupling of the He 2s2p (1P0) and 2p2 (1Se) double excitation states with 800 nm light
• Photoabsorption of attosecond XUV light pulses by two strongly laser-coupled autoionizing states
• Quantum Coherence in Photo-Ionization with Tailored XUV Pulses

Cited by in corpus (3)

• Multi-polariton control in attosecond transient absorption of autoionizing states
• Ionic Coherence in Resonant Above-Threshold Attosecond Ionization Spectroscopy
• Probing coherent electronic superpositions of singly- and doubly-excited states of krypton with attosecond four-wave mixing spectroscopy