Impurity-related optical response in a 2D and 3D quantum dot with Gaussian confinement under intense laser field

ABSTRACT

Using the two-dimensional (2D) diagonalisation method, the impurity-related electronic states and optical response in a 2D quantum dot with Gaussian confinement potential under nonresonant intense laser field are investigated. The effects of a hydrogenic impurity on the energy spectrum and binding energy of the electron and also intersubband optical absorption are calculated. The obtained numerical results show that the degeneracies of the excited electron states are broken and the absorption spectrum exhibits a redshift with the values of the laser field. The findings indicate a new degree of freedom to tune the performance of novel optoelectronic devices, based on the quantum dots and to control their specific properties by means of intense laser field and hydrogenic donor impurity. Using the same Gaussian confinement model, the electronic properties of a confined electron in the region of a spherical quantum dot are studied under the combined effects of on-centre donor impurity and a linearly polarised intense laser radiation. The three-dimensional problem is used to theoretically model, with very good agreement, some experimental findings reported in the literature related to the photoluminescence peak energy transition.

KEYWORDS:

• Gaussian quantum dot
• nonresonant intense laser field
• optical absorption

Acknowledgments

C. A. Duque is grateful to the Colombian Agencies: CODI-Universidad de Antioquia (Estrategia de Sostenibilidad de la Universidad de Antioquia and projects ”Propiedades magneto-ópticas y óptica no lineal en superredes de Grafeno” and ”Estudio de propiedades ópticas en sistemas semiconductores de dimensiones nanoscópicas”), and Facultad de Ciencias Exactas y Naturales-Universidad de Antioquia (CAD exclusive dedication projects 2018–2019). C. A. Duque also acknowledges the financial support from El Patrimonio Autónomo Fondo Nacional de Financiamiento para la Ciencia, la Tecnología y la Innovación Francisco José de Caldas (project 80740-173-2019).

Disclosure statement

No potential conflict of interest was reported by the authors.