Band structure and band offsets in Zn_1-xCd_xSe/ZnSe quantum wells

The sensitivity of interband and intersubband transition energies to the valence-band offset in Zn_1-xCd_xSe/ZnSe quantum wells is investigated. Interconduction-band transition energies between the first two conduction subband levels is shown to give the optimum sensitivity. By using the valence-band offset, Q_v, as an adjustable parameter we are able to fit calculations to experiment and determine a Q_v value of 0.31. To calculate the band structure in the quantum well we use an 8 × 8 k · p method which takes into account valence-subband-mixing, nonparabolicity and strain effects.