Abstract

With emerging new semiconductor superlattice structures it is important to evaluate their characteristics with emphasis on interfacial quality, particularly in the limit of very thin constituent layers (< 100 A). We report here on transient luminescence studies of new II-VI compound semiconductors quantum well structures, with two examples based on the ZnSe/(Zn,Mn)Se and CdTe/ZnTe heterostructures (1). In this work we have employed a tunable high repetition rate picosecond source in the blue and red regions of the spectrum. An optimum compromise for temporal broadening in the spectrosopic measurements was reached by using a spectrometer with a pair of gratings in the subtractive mode, enjoined with a Hamamatsu synchroscan streak camera. In this way a temporal/spectral resolution of approximately of 10 psec/5 A was achieved. As a consequence, time-resolved spectra from the quantum well structures has yielded direct information of key energy relaxation and localization processes of excitons.

© 1986 Optical Society of America