DEFECT-EXCITATION PROCESSES INVOLVED IN LASER-INDUCED ATOMIC-EMISSIONAND LASER-ABLATION OF NONMETALLIC SOLIDS

A microscopic theory of defect-induced emission of atoms from nonmetal lic surfaces is presented. The results agree very well with the experi mental results for the emission yield with the number of laser shots, laser fluence, and incident photon energy. Our results show that the e mission of atoms at low photon energy and laser fluence originates onl y from the surface defects like adatoms and steps. Such emissions cann ot be observed from the defect-free surfaces of semiconductors conside red here.