Effects of Spatial Dispersion in Symmetric and Asymmetric Semiconductor Quantum Wells

Abstract

Effects of spatial dispersion in quantum wells are discovered and investigated in detail in reflection experiments. We studied oblique incidence of pure s and p polarized light which has been reflected elliptically polarized. The polarization degree of the reflected light is governed by the in-plane photon momentum which is the distinctive feature of the spatial dispersion effects. The effects of spatial dispersion are allowed by symmetry in inversionasymmetric systems only. Therefore we investigated bulk-inversion asymmetric ZnSe/ZnMgSSe and structure-asymmetric GaAs/AlGaAs and CdZnTe/ CdTe/CdMgTe quantum wells. We studied the reflected light polarization state in the vicinity of the heavy-and light-exciton resonances where the spatial dispersion effects are resonantly enhanced.

Manifestation of interface anisotropy in CdTe quantum wells

“…At oblique incidence of light, in both structures, the phenomenon of polarization conversion from linear to circular was observed. This phenomenon is related to the gyrotropy of quantum wells [11] and was studied in detail in our previous works [12,13]. No polarization conversion was observed in the structure with symmetric barriers at normal light incidence [13].…”

“…This phenomenon is related to the gyrotropy of quantum wells [11] and was studied in detail in our previous works [12,13]. No polarization conversion was observed in the structure with symmetric barriers at normal light incidence [13]. The degree of circular polarization was only a few percent at oblique light incidence [13].…”

“…No polarization conversion was observed in the structure with symmetric barriers at normal light incidence [13]. The degree of circular polarization was only a few percent at oblique light incidence [13].…”

Проявление анизотропии интерфейсов в квантовых ямах CdTe/CdZnTe

“…При наклонном падении света наблюдалось явление конверсии поляризаций из линейной в циркулярную. Это явление связано с гиротропией квантовых ям и было детально исследовано в наших предыдущих работах [10,11]. При нормальном падении света в структуре с симметричными барьерами конверсии поляризаций не наблюдалось, а при наклонном падении света степень круговой поляризации составляла всего несколько процентов [12].…”