Formulation of "Exciton in a Quantum Box Model" for Multiple Exciton Generation Solar Cell Applications

H.I. Ikeri¹ , A.I. Onyia² , P.U. Asogwa³

Section:Research Paper, Product Type: Journal-Paper
Vol.8 , Issue.4 , pp.35-40, Aug-2020

Online published on Aug 31, 2020

Copyright © H.I. Ikeri, A.I. Onyia, P.U. Asogwa . This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
 

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Abstract :
Exciton in a quantum box model for multiple exciton generation solar cell applications is successfully formulated. We have modeled quantum dot QD as a quantum box and then solved the time independent Schr?dinger Equation to determine the Eigen state energies of the confined exciton. In broader perspective the model contributes to the better understanding of the working principles of multiple exciton solar cells and enables the improvement of their performances. The results obtained strongly reveal that multiple exciton generation is more efficient in QDs because of the enhanced Coulomb interaction between the exciton, slow hot exciton cooling and relaxed momentum conservation due to quantum confinement effects. These novel properties allow for proper utilization of the hot exciton created by the absorption of high energetic photons to generate more excitons instead of losing the excess energy to phonon emission. The creation of additional excitons dramatically minimizes the spectral losses due to thermalization which characterized the conventional device thus making it possible to absorb and utilize supra band photons suitable for high efficient multiple exciton generation solar cells. This produces significant increase in solar to electricity conversion efficiencies in the form of increased photo generated current

Key-Words / Index Term :
Theoretical model, Quantum dot, Multiple exciton generation, Excitons, Quantum confinement, Solar cells, Potential well and Schr?dinger Equation

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