TRANSIENT-RESPONSE OF GALLIUM-ARSENIDE AND SILICON SOLAR-CELLS UNDER LASER-PULSE

Solar cells can be used as receivers in laser power beaming applicatio ns[1]. Power beamed to a photovoltaic array could power a satellite, a n orbital transfer vehicle or a lunar base. Understanding solar cell r esponse to the pulsed output of a free-electron laser (FEL) is importa nt for evaluation of power-beaming applications. In this work we inves tigate the time response of gallium arsenide and silicon solar cells t o a 25 ns monochromatic pulse input. The PC-ID computer code is used t o analyze the cell current during and after the pulse for various cond itions. For GaAs cells, current decay was studied at 511, 840 and 870 nm, Most of the results have been calculated for a peak intensity of 5 0 W cm(-2) which corresponds to roughly 500 suns peak concentration. S ilicon cells have a longer minority carrier lifetime and weaker optica l absorption, resulting in longer characteristic time constants. Si ce ll performance was studied at 900, 950 and 1060 nm wavelengths. (C) 19 98 Published by Elsevier Science Ltd. All rights reserved.