Numerical analysis of transient photoconductivity in insulators

Abstract

The nonlinear partial differential equations which describe transient photoconductivity in insulators are solved numerically. Trapping and recombination are included which allows photoconduction to be studied in the presence of large space charge. Use of methods for ‘‘stiff’’ differential equations insures stable time dependent solutions even for problems which have widely different time constants. The program is applied to a thin film (1000 Å) of silicon dioxide to illustrate the salient features of the numerical solutions and the capabilities of the program.

Hole Transport in Poly(phenylene vinylene)/Methanofullerene Bulk‐Heterojunction Solar Cells

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Field and temperature dependence of the photocurrent in polymer/fullerene bulk heterojunction solar cells

“…Actually, this calculation reproduces the analytical result of Sokel and Hughes. 8,14 From the difference between the dashed and dashed-dotted line, it is evident that Langevin recombination is the dominant loss mechanism in the entire measured bias range.…”

Light intensity dependence of open-circuit voltage of polymer:fullerene solar cells

“…This behavior is caused by the opposite effect of drift and diffusion of charge carriers. 11 At V oc drift and diffusion balance and the current is zero. At higher effective voltage V oc − V Ͼ 0.1 V the drift contribution is dominant and the photogenerated current tends to saturate.…”