In this work, we will discuss Si-/SiGe and high-κ oxides nanostructures. The exciton properties of strained Si/Si1-χGeχ quantum well (QW) are calculated taking into account interface effects and both possibilities of the band lineup of the conduction-band offset, type-I and type-II. Our
numerical results show that interface fluctuations of only 10 Å in a Si/Si1-χGeχ 50 Å type-I QW (type-II QW) leads to a 25 meV (10 meV) blueshift of the exciton (transition) energy. Concerning high- κ nanostructures, our simulation was performed in order to analyse how the charge image effects can modify the electronics properties in Si/HfO2 and Si/SrTiO3 based quantum wells. The results of Si/SrTiO3 (Si/HfO2) quantum wells indicate a recombination emission difference, as compared with the case when no charge image effects are included, of the order of 1.5 eV (0.7 eV).
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