Raman interferometry between autoionizing states to probe ultrafast wavepacket dynamics with high spectral resolution

TL;DR

This paper introduces a Raman interferometry technique that achieves high spectral and temporal resolution to study ultrafast electron wavepacket dynamics, demonstrated on argon autoionizing states with excellent experimental and theoretical agreement.

Contribution

The study presents a novel spectroscopic method combining Raman interference with electron yield monitoring for high-resolution ultrafast electron dynamics analysis.

Findings

Resolved argon autoionizing state composition and evolution in detail

Achieved high spectral and temporal resolution simultaneously

Theoretical models agree closely with experimental results

Abstract

Photoelectron interferometry with femto- and atto-second light pulses is a powerful probe of the fast electron wavepacket dynamics, albeit it has practical limitations on the energy resolution. We show that one can simultaneously obtain both high temporal and spectral resolution by stimulating Raman interferences with one light pulse and monitoring the differential changes in the electron yield in a separate step. Applying this spectroscopic approach to the autoionizing states of argon, we experimentally resolved its electronic composition and time-evolution in exquisite detail. Theoretical calculations show remarkable agreement with the observations and shed light on the light-matter interaction parameters. Using appropriate Raman probing and delayed detection steps, this technique enables highly dfferential probing and control of electron dynamics in complex systems.