Symmetrical ZnSen/CdSen superlattices, where n (= 2 to 6) was the number of monolayers, were prepared by using a new growth method: self-limiting monolayer epitaxy. When n was less than or equal to 3, the low-temperature photoluminescence spectra of these superlattices were dominated by near-bandgap emissions, with full widths at half maximum of 0.017eV. After longer periods, the photoluminescence intensity fell sharply and the above widths increased by a factor of 2. This was attributed to the formation of misfit dislocations. The energetic positions of the photoluminescence peaks were in good agreement with transition energy calculations which were based upon a Kronig-Penney type of model.

P.Juza, H.Zajicek, H.Sitter, M.Helm, W.Faschinger, K.Lischka: Applied Physics Letters, 1992, 61[26], 3133-5