Potentially modulated multi-quantum well solar cells with improved dark current characteristics

The predicted performance of multi-quantum well (MQW) solar cells relies not only on a high material quality with minimum non-radiative recombination losses at QWs heterointerfaces, but also an efficient escape rate of photo-generated carriers out of QWs into the "base" region with minimum radiative losses within QWs. We propose and investigate potentially modulated InGaAs/GaAs MQW solar cells, for which the MQW structure is modified from a series of conventional square-shaped QWs to step-like modulated QWs. We show that radiative recombination and forward-bias dark currents are significantly reduced in potentially modulated MQW solar cells.