EXCITONIC PROPERTIES AND MAGNETOOPTICAL CHARACTERIZATION OF (ZN, CD)SE ZNSE HETEROSTRUCTURES/

We present an experimental and theoretical study of optical and magnet ooptical properties of excitons in strained layer ZnCdSe-ZnSe superlat tices. The optical characterizations of these structures are based on photoluminescence and reflectivity measurements at 2 K. The excitonic transition energies are determined experimentally and are found in agr eement with the predictions of the envelope function, taking into acco unt band offsets and exciton binding energies. These binding energies and also the oscillator strengths are calculated using a recent formal ism of fractional dimensional space (alpha D) and compare favourably w ith variational calculations. Magnetoreflectivity measurements are per formed up to 5.5 T. They permit us to calculate the Zeeman splitting o f \+/- 3/2, +/- 1/2] and \+/- 1/2, -/+ 1/2] transitions and then, to d educe the corresponding effective g-values g(3/2) and g(1/2). In our k nowledge, our results concerning the calculations of Delta E-1/2 and t hen g(1/2) for such superlattices are the first ones and permit us to confirm the interlevel mixing in these structures. (C) 1997 Elsevier S cience Ltd.