Volume 15, Issue 10 · IJARST · ISSN 2319-1783 / 2320-1126

Theoretical Study of Spin-Orbit Interaction in CdSe/CdS core-shell elliptical quantum dots Subjected to External Magnetic Fields

Theoretical Study of Spin-Orbit Interaction in CdSe/CdS core-shell elliptical quantum dots Subjected to External Magnetic Fields is an open-access, peer-reviewed research paper by Ahmed Ibrahim Farhan, published in Volume 15, Issue 10 of the International Journal of Advanced Research in Science and Technology (IJARST), a UGC-approved journal (Print ISSN 2319-1783, Online ISSN 2320-1126).

Author

Ahmed Ibrahim Farhan

Abstract

This work presents a complete numerical study of confined electron states in CdSe/CdS core–shell elliptical quantum dots, within the single-band effective mass approximation and BenDaniel–Duke Hamiltonian. The position-dependent effective mass is used for a correct description of carrier transport through the CdSe/CdS heterointerface and the two-dimensional Schrodinger equation under finite confinement conditions is discretized and solved by the finite difference method. The developed numerical framework is applied to study the influence of the quantum dot geometry on its electronic properties. In particular, the influences of core size, shell thickness, and aspect ratio on the confined energy levels and electron wavefunctions are studied systematically. Contour plots, 3D surface visualizations, and 1D cross-sectional profiles of the spatial distribution of the ground and excited states are used to demonstrate the localization behavior of the confined electron. In addition, a mesh convergence study is conducted to confirm the numerical accuracy and stability of the proposed method. The effect of the geometric deformation on quantum confinement is examined by comparing elliptical and circular quantum dots. The results show that the increase of core size reduces the confinement strength and hence the confined electron energy levels. The effects of the changes in shell thickness and aspect ratio are also reflected in the energy spectrum and spatial localization of the electron wavefunctions. The results show that the electronic structure depends strongly on the quantum dot geometry. The proposed computational framework provides an accurate and computationally efficient tool for analysis and design of semiconductor core-shell quantum dots and can be readily extended to consider more advanced nanostructures involving external electric and magnetic fields, spin-related effects and excitonic interactions.

Keywords: CdSe/CdS core-shell quantum dots; Elliptical quantum dots; Effective mass approximation; BenDaniel–Duke Hamiltonian; Finite difference method; Position-dependent effective mass; Quantum confinement; Energy spectrum; Electron wavefunction; Semiconductor nanostructures

DOI: https://doi.org/10.62226/ijarst20262849

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DOI

10.62226/ijarst20262849

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How do you cite this paper?

Ahmed Ibrahim Farhan — “Theoretical Study of Spin-Orbit Interaction in CdSe/CdS core-shell elliptical quantum dots Subjected to External Magnetic Fields.” International Journal of Advanced Research in Science and Technology (IJARST), Volume 15, Issue 10. DOI: 10.62226/ijarst20262849.

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