EXCITONIC SIDE BANDS OF INNER-SHELL EXCITATIONS IN RARE GAS SOLIDS

Abstract

Valence-exciton luminescence under inner-shell excitation of the rare gas solids Xe, Kr, and Ar has been measured using time-resolved photoluminescence. Two different processes for exciton creation can be distinguished: creation of "prompt" excitons immediately after excitation (within the experimental time resolution), and creation of "delayed" excitons through electron–hole recombination. The decay structure of the exciton emission in the range of inner-shell excitation is characterized by the coexistence of the two processes. Time-resolved excitation spectra near the 2p edge in Ar, the 3d edge in Kr, and the 4d edge in Xe are discussed. The process of prompt exciton creation is strongly enhanced above an excitation threshold at the energy position of the ionization limit of the core state plus the energy of the valence free exciton.