Role of dynamic depolarization for the intersubband resonance in the localization regime

We study theoretically the intersubband ͑IS͒ absorption spectrum of electrons in a center-doped quantum well ͑QW͒ as a function of the carrier density. Besides the subband quantization in z direction, the wave functions of the electrons, being directly exposed to the charged dopands, become disorder localized in the layer plane. For each set of random impurity configurations, the corresponding spectrum of quantum states is computed with a self-consistent density-functional approach, thus, taking into account the disorder and nonlinear static screening effects in a realistic way. On the basis of these effective single-particle states, we then include dynamic many-body effects ͑depolarization and dynamic exchange corrections͒ by applying and extending our recently developed theory of resonant screening in the localization regime. We analyze the relevance of the various many-body effects and find that at higher electron densities the direct static Hartree and the depolarization contributions dominate over the exchange effects. Dynamic Coulomb interactions qualitatively change the IS absorption spectrum of the statically screened electron gas, however, do not lead to a spectral narrowing in this system. A small variation of the ␦n-layer position within the QW affects the relative disorder strength of the two subbands and causes dramatic changes of the spectral shape and width. Our model and results are suitable for a direct comparison with experimental data.

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Role of dynamic depolarization for the intersubband resonance in the localization regime

Cited by 3 publications

References 10 publications

Collective plasma response of interacting electrons localized in disordered GaAs/AlGaAs superlattices

Collective plasma response of interacting electrons localized in disordered GaAs/AlGaAs superlattices

Collective plasma response of interacting electrons localized in disorderedGaAs/AlxGa1−x
Pusep
¹
,
Fortunato
²
,
González‐Borrero
³

et al. 2001
Phys. Rev. B
7
0
9
0
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Density-dependent intersubband absorption in strongly disordered systems

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Role of dynamic depolarization for the intersubband resonance in the localization regime

Cited by 3 publications

References 10 publications

Collective plasma response of interacting electrons localized in disordered GaAs/AlGaAs superlattices

Collective plasma response of interacting electrons localized in disordered GaAs/AlGaAs superlattices

Collective plasma response of interacting electrons localized in disorderedGaAs/AlxGa1−xPusep1, Fortunato2, González‐Borrero3 et al. 2001Phys. Rev. B7090View full textAdd to dashboardCite

Density-dependent intersubband absorption in strongly disordered systems

Contact Info

Product

Resources

About

Collective plasma response of interacting electrons localized in disorderedGaAs/AlxGa1−x
Pusep
¹
,
Fortunato
²
,
González‐Borrero
³

et al. 2001
Phys. Rev. B
7
0
9
0
View full text Add to dashboard Cite