Laser pulses for coherent xuv Raman excitation

TL;DR

This paper develops optimized laser pulse sequences using quantum control and electronic structure theory to coherently excite valence states in neon, enabling potential applications in multidimensional xuv and x-ray spectroscopy.

Contribution

It introduces a novel combination of multi-channel electronic structure calculations with quantum optimal control for designing Raman pulses in the xuv regime.

Findings

Achieved up to 13% population of the valence excited state in neon.

Demonstrated control over superpositions with up to 4.5% population and phase.

Established a pathway for core-hole excitation in molecules for advanced spectroscopy.

Abstract

We combine multi-channel electronic structure theory with quantum optimal control to derive Raman pulse sequences that coherently populate a valence excited state. For a neon atom, Raman target populations of up to 13% are obtained. Superpositions of the ground and valence Raman states with a controllable relative phase are found to be reachable with up to 4.5% population and phase control facilitated by the pump pulse carrier envelope phase. Our results open a route to creating core-hole excitations in molecules and aggregates that locally address specific atoms and represent the first step towards realization of multidimensional spectroscopy in the xuv and x-ray regimes.