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Self-polarization effects in spherical inverted core–shell quantum dot

  • D. Stojanović
  • R. Kostić
Article
  • 69 Downloads
Part of the following topical collections:
  1. Focus on Optics and Bio-photonics, Photonica 2017

Abstract

Single electron in spherical shell in infinite potential barrier is investigated. Schrödinger equation in effective mass approximation for this spherical heterosystem is solved to get eigenenergies and corresponding wave functions. In case of infinite potential barrier the ground state energy depends only on the shell width. Self-polarization potential is obtained by solving Poisson equation in three concentric spherical regions: core, shell and surrounding medium. Shell self-polarization energy depends on geometry (core and shell radius) and the dielectric mismatch at the quantum dot boundaries. Self-polarization energy is used as perturbation. One electron ground state energy results are presented in this paper. CdSe is placed in the shell. Surrounding medium is dielectric of smaller permittivity (vacuum or water), that is the most realistic case. The core dielectric permittivity influence on ground state energy is analysed. The self-polarization corrections to the ground state energy for different compositions, i.e. core and shell radius, are presented. For smaller core radius and the same shell thickness (which imply the same unperturbed ground state energy) bigger is the energy correction, i.e. perturbed energy state, for fixed value of the core dielectric permittivity. Increase of core dielectric permittivity produces decrease of energy correction.

Keywords

Core/shell nanostructure Poisson equation Self-polarization energy 

Notes

Acknowledgements

This work is supported by Serbian Ministry of Education and Science, under Projects No. III45003.

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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Institute of PhysicsUniversity of BelgradeBelgradeSerbia

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