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

TL;DR

This paper theoretically investigates the electronic continuum states and far infrared absorption of InAs/GaAs quantum dots, analyzing the effects of magnetic fields and potential for designing strong in-plane absorbers.

Contribution

It provides a theoretical analysis of continuum states and absorption spectra in InAs/GaAs quantum dots, including magnetic field effects and design implications.

Findings

Infrared absorption is insensitive to magnetic fields due to dot flatness.

Continuum states reorganize into quasi-Landau series under magnetic fields.

Potential for designing InAs/GaAs photoconductors with strong in-plane absorption.

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.