Strain induced optical properties of exciton in a CdTe/ZnTe quantum dot

Abstract

The influence of strain on the binding energies of heavy and light hole is obtained in a ZnxCd1−xTe/ZnTe quantum dot taking into account the phonon confinement effect. The band offsets are calculated using model-solid approach. The dielectric mismatch effect is introduced between the dielectric constants of dot and the barrier. The strain induced energies of excitonic transitions in a CdZnTe quantum dot with ZnTe barrier are brought out considering the internal electric field induced by the spontaneous and piezoelectric polarizations. Calculations have been obtained using Bessel function as an orthonormal basis for different confinement potentials of barrier height, strain induced linear and third-order nonlinear optical absorption coefficients and the changes of refractive index with the incident photon energy are observed. Our results show that the exciton binding energy is enhanced with the inclusion of potential taking into account the effects of dielectric mismatch and the geometry of quantum dot with various Zinc alloy content has a great influence on the optical properties of the dot.