Spatial Coherence of Core Holes in Resonant X-Ray Emission for a Model of Diatomic Molecule with Dephasing

Abstract

The effect of localization of core holes due to dephasing in the resonantx-ray emission spectrum is investigated theoretically by applying thestochastic theory to a simplified model of diatomic molecule.The x-ray emission spectrum from the occupied molecular orbitals iscalculated under the condition that the core electron is excited resonantlyto one of the unoccupied molecular orbitals.It is found that, as the relaxation time of the relative phase between theatomic wave functions of the core orbitals becomes short as compared withthe core hole lifetime, the parity-broken luminescence gains its intensityindicating the partial localization of the core hole.Although the dephasing in the outer orbitals also contributes to thesymmetry breaking, its influence is relatively small due to the motionalnarrowing effect.