Excitonic properties and magnetooptical characterization of (Zn, Cd)Se/ZnSe heterostructures

We present an experimental and theoretical study of optical and magnetooptical properties of excitons in strained layer ZnCdSe-ZnSe superlattices. 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 agreement with the predictions of the envelope function, taking into account band offsets and exciton binding energies. These binding energies and also the oscillator strengths are calculated using a recent formalism of fractional dimensional space (alpha D) and compare favourably with variational calculations. Magnetoreflectivity measurements are performed up to 5.5 T. They permit us to calculate the Zeeman splitting of \+/- 3/2, +/- 1/2] and \+/- 1/2, -/+ 1/2] transitions and then, to deduce the corresponding effective g-values g(3/2) and g(1/2). In our knowledge, our results concerning the calculations of Delta E(1/2) and then g(1/2) for such superlattices are the first ones and permit us to confirm the interlevel mixing in these structures. (C) 1997 Elsevier Science Ltd.