Photo-stimulated Rebuilding of Structure in Semiconductors

Abstract

A strong electron-phonon interaction observed in semiconductors allows to realize a special kind of atomic rebuilding under photo-irradiation of the medium. We consider three types of defective structures: one atomic, two-atomic (“dump-bell”) and multi-atomic (kinks) defects. It is shown that an inversion effect of the defect potential term may be realized if there are non-equivalent neighboring positions of one-atomic and two-atomic defects. In this case the photo-excitation of electronic subsystems of these defects leads to an inversion of potential terms and a consecutive athermal rebuilding of the defective structures. The Yahn-Teller effect and psevdo-effect play a special role here. It is shown for kink-structures that the photo-excitation of the electronic subsystems results in the alteration of kink nonius and the successive exponentially strong decrease of an activation barrier. Especially effects of athermal atomic rebuilding of U-negative defects are considerable.