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The present paper is aimed to investigate theoretically the quantum confinement inCd1−xZnxS-related quantum dots withxthe atomic fraction of Zn. For both electrons and holes, we have calculated the excited bound states with use of the spherical geometry model and assuming a finite potential at the boundary. For electrons, calculations were made by using Bessel function as an orthonormal basis. However, for holes, the confined subbands have been calculated based on squared quantum well envelope wave functions. The subband energies were evaluated for both electrons and holes versus zinc composition as well.

This work reports on a theoretical study of superlattices based on Cd 1-x Zn x S quantum dots embedded in an insulating material. This system, assumed to a series of flattened cylindrical quantum dots with a finite barrier at the boundary, is studied using the tight binding approximation. The electronic states of  1 Γ miniband have been computed as a function of zinc composition for different inter-quantum dot separations. Calculations have been made for electrons, heavy holes and light holes. Three main features were revealed: (i) in the case of electrons, the Zn composition x = 0.4 is expected to be the most favorable to give rise a superlattice behavior for the Cd 1-x Zn x S quantum dots studied (ii) the strong localization character of heavy holes is evident in the Cd 1-x Zn x S nanostructures (iii) the Cd 0.2 Zn 0.8 S system is the more appropriate to exhibit a superlattice behavior for light holes especially when the superlattice period is low.

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