EXCITONIC ENERGY-TRANSFER PROCESS IN NE-KR ALLOY STUDIED BY PHOTON-STIMULATED DESORPTION OF METASTABLE ATOMS

Metastable atom desorption from a pure solid Ne and a solid Ne-Kr allo y has been systematically studied using a monochromatic synchrotron ra diation. Refined time-of-flight spectrometer enabled us to investigate the desorption mechanism in more detail. Metastable Ne atoms desorbed through cavity ejection mechanism by the excitation of the first orde r surface, and the first and the second order bulk excitons are found to have almost the same kinetic energy, E(k) = 0.18 +/- 0.02 eV, while by 2p(5)3p type surface exciton, E(k) = 0.21 +/- 0.02 eV. By the exci tation of Ne bulk exciton in Ne-Kr alloy, effective excitonic energy t ransfer process has been observed, which results in the decrease of th e Ne desorption yield by the bulk excitation.