Performance of InGaAs metamorphic laser power converters at different conditions

Abstract

The topic of the work is the metamorphic InGaAs heterostructures for laser power converters (LPC) and their performance at different measurement conditions. Three different illumination conditions were studied: monochromatic Xe-lamp uniform illumination, laser with quasi-uniform illumination (with laser beam unfocusing) and non-uniform focused laser illumination. For simulating the experimental IV-curves as well as FF-Jg, Voc-Jg and η-Jg dependences, a tube model developed earlier and describing the charge carrier transport along current lines was used for all three illumination regimes. In the absence of losses (Xe-lamp and unfocused laser), the perfect model simulation model exhibiting an experimental efficiency greater than 50% (for λ=1064nm) has been demonstrated. As a result of simulation of LPC characteristics obtained under focused laser illumination, the losses associated with uniform light distribution as well as with an additional resistance, which decrease the LPC efficiency, have been found.