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Title: Nonlinear effects in modeling thin-film graded-bandgap solar cells
We model the e ect of concentrated sunlight on CIGS thin- lm graded-bandgap solar cells using an optoelectronic numerical model. For this purpose it is necessary  first to solve the time-harmonic Maxwell equations to compute the electric  eld in the device due to sunlight and so obtain the electron-hole-pair generation rate. The generation rate is then used as input to a drift-diffusion model governing the flow of electrons and holes in the semiconductor components that predicts the current generated. The optical submodel is linear; however, the electrical submodel is nonlinear. Because the Shockley{Read{Hall contribution to the electron-hole recombination rate increases almost linearly at high electron/hole densities, the effciency of the solar cell can improve with sunlight concentration. This is illustrated via a numerical study.  more » « less
Award ID(s):
2011603 2011996
PAR ID:
10429383
Author(s) / Creator(s):
; ; ;
Editor(s):
Subramania, Ganapathi S.; Foteinopoulou, Stavroula
Date Published:
Journal Name:
Proc. SPIE 12196, Active Photonic Platforms 2022
Volume:
121960D
Page Range / eLocation ID:
81
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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