 Fig. 1. A pronounced absorption enhancement (~100) produced by spheroidal silver nanoparticles in gallium arsenide (GaAs) can be used to increase photocurrent generation in quantum-dot intermediate-band solar cells (Luque A. et al 2004). Mendes MJ et al 2009 use the electrostatic approximation (for example, Bohren CF and Huffman 1983, pp. 136-152) to calculate the aspect ratio of the nanospheroid that produces the maximum enhancement at each photon energy (see also Fig. 3 in Mendes MJ et al 2009). Since metallic particles in a semiconducting medium (such as GaAs) can promote electron-hole recombination at their surfaces, the effect of an insulating coating on the nanoparticles was also considered by Mendes MJ et al. Such a coating prevents recombination while allowing a sufficiently high absorption enhancement (~10) in the nanoparticle vicinity. The figure reproduced by permission from Mendes MJ et al 2009 with minor modifications. [MJM]
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