Carrier states and optical response in core–shell-like semiconductor nanostructures

Abstract

The charge carrier states in a GaAs/AlGaAs axially symmetric core–shell quantum wire are calculated in the effective mass approximation via a spectral method. The possible presence of externally applied electric and magnetic fields is taken into account, together with the variation in the characteristic in-plane dimensions of the structure. The obtained energy spectrum is used to evaluate the optical response through the coefficients of intersubband optical absorption and relative refractive index change. The particular geometry of the system also allows to use the same theoretical model in order to determine the photoluminescence peak energies associated to correlated electron-hole states in double GaAs/AlGaAs quantum rings, showing a good agreement when they are compared with recent experimental reports. This agreement may validate the use of both the calculation process and the approximate model of abrupt, circularly shaped cross section geometry for the system.

Keywords:

• Core–shell
• quantum wires and rings
• electron states
• optical response

Acknowledgements

The authors are grateful to the Colombian Agencies CODI-Universidad de Antioquia (project: ‘Manipulación de propiedades optoelectrónicas de nanoestructuras semiconductoras por ondas acústicas superficiales.’) and Facultad de Ciencias Exactas y Naturales-Universidad de Antioquia (CAD exclusive dedication project 2016-2017).

Notes

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by Facultad de Ciencias Exactas y Naturales-Universidad de Antioquia [CAD exclusive dedication project 2016-2017].