Luminescent coupling in planar opto-electronic devices

• Published in: Journal of applied physics 2015-10, Vol.118 (14)
• Main Authors: Wilkins, Matthew, Valdivia, Christopher E., Gabr, Ahmed M., Masson, Denis, Fafard, Simon, Hinzer, Karin
• Format: Article
• Language: English
• Subjects: ABSORPTION; Applied physics; CARRIERS; CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; Computer simulation; Continuity equation; CONTINUITY EQUATIONS; Coupling; DESIGN; DIAGRAMS; DIFFUSION; Electronic devices; ELECTRONIC EQUIPMENT; Energy conversion efficiency; GALLIUM ARSENIDES; LUMINESCENCE; Modelling; MONOCHROMATIC RADIATION; Optoelectronic devices; PHOTONS; QUANTUM EFFICIENCY; SEMICONDUCTOR JUNCTIONS; SIMULATION
• ISSN: 0021-8979; 1089-7550
• DOI: 10.1063/1.4932660

Effects of luminescent coupling are observed in monolithic 5 V, five-junction GaAs phototransducers. Power conversion efficiency was measured at 61.6% ± 3% under the continuous, monochromatic illumination for which they were designed. Modeling shows that photon recycling can account for up to 350 mV of photovoltage in these devices. Drift-diffusion based simulations including a luminescent coupling term in the continuity equation show a broadening of the internal quantum efficiency curve which agrees well with experimental measurements. Luminescent coupling is shown to expand the spectral bandwidth of the phototransducer by a factor of at least 3.5 for devices with three or more junctions, even in cases where multiple absorption/emission events are required to transfer excess carriers into the limiting junction. We present a detailed description of the novel luminescent coupling modeling technique used to predict these performance enhancements.