RADIATIVE RECOMBINATION TRANSITIONS BETWEEN STATES OF BOUND AND FREE-EXCITONS IN UNIAXIALLY STRAINED CADMIUM TELLURIDE

The way that emission lines from bound and free excitons in CdTe shift , split, and change in intensity under uniaxial strain have been inves tigated theoretically and experimentally. The nonlinear shift observed in the energy positions of peaks due to receptor-bound excitons is ca used by strong spin-spin interaction in the system of two heavy holes. A nonmonotonic dependence and abrupt quenching of the intensity of em ission from acceptor-bound excitons in the high-strain regime (pressur es P>1 kbar) with a simultaneous buildup in the free-exciton emission line has been observed. The theoretical model considers two basic mech anisms for recombination-radiative and Auger recombination. The result s which were obtained can be used to identify types of defects in CdTe , and to determine local mechanical stresses in CdTe-based heterostruc tures. (C) 1995 American Institute of Physics.