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Electronic continuum states and far infrared absorption of InAs/GaAs quantum dots

Duc Phuong Nguyen·Nicolas Regnault·Robson Ferreira·Gerald Bastard
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Abstract

The electronic continuum states of InAs/GaAs semiconductor quantum dots embedded in a GaAs/AlAs superlattice are theoretically investigated and the far infrared absorption spectra are calculated for a variety of structures and polarizations. The effect of a strong magnetic field applied parallel to the growth direction is also investigated. We predict that the flatness of the InAs/GaAs dots leads to a far infrared absorption which is almost insensitive to the magnetic field, in spite of the reorganization of the continuum into series of quasi-Landau states. We also predict that it is possible to design InAs/GaAs photoconductors which display very strong in-plane absorption.

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Duc Phuong Nguyen, Nicolas Regnault, Robson Ferreira, Gerald Bastard. 2005-07-11. Electronic continuum states and far infrared absorption of InAs/GaAs quantum dots. https://doi.org/10.1103/physrevb.71.245329

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