Objective The GalnP/GaAs/Ge tandem triple junction cells are the highest efficiency photovoltaic (PV) devices and are likely to be the first of the "Third Generation" cells to enter the terrestrial PV market in concentrator applications. They employ three different solar cells stacked on top of each other to capture and convert a wider spectral range of solar radiation to electricity. The commercial viability of concentrator systems depends crucially on the use of the highest efficiency cells. The Strain-Balanced Quantum Well Solar Cell (SB-QWSC) is an innovative, nanostructured cell, pioneered by the Quantum Photovoltaic Group (QPG) at Imperial College, which has the potential to enhance the efficiency of the triple junction cell significantly by replacing the GaAs cell. The SB-QWSC increases tandem efficiency by reducing the absorption band-gap of GaAs resulting in better utilisation of the solar spectrum. Recent experimental and theoretical work based onphotoluminescence (PL), photoconductivity (PC) and electroluminescence (EL) studies have revealed that the Quasi-Fermi Level Separation (QFLS) in single quantum well (SQW) devices is smaller than expected in both the dark and the light. This implies lower recombination and hence enhanced efficiency. Furthermore, the SB-QWSC dark currents at concentrator current levels show ideality factor n=1. This suggests that minimum non-radiative recombination levels can be achieved in SB-QWSC. Finally the exciting possibility of efficiency enhancement by photon recycling can also be considered as the unavoidable radiative energy would be re-absorbed in other wells in a light-trapping environment. There is therefore a great need to clarify the mechanisms behind the general efficiency enhancement in the SB-QWSC. This will be done by extending the recent studies on QFLS in SQW devices under light illumination to SB-QWSCs. Fields of science engineering and technologyenvironmental engineeringwaste managementwaste treatment processesrecyclingnatural sciencesearth and related environmental sciencesatmospheric sciencesmeteorologysolar radiationengineering and technologyenvironmental engineeringenergy and fuelsrenewable energysolar energyphotovoltaicnatural sciencesphysical sciencestheoretical physicsparticle physicsphotons Keywords Electroluminescence Fermi levels Nanostructures Photoluminescence Photovoltaics Quantum Well Solar Cells Solar concentrators Programme(s) FP6-MOBILITY - Human resources and Mobility in the specific programme for research, technological development and demonstration "Structuring the European Research Area" under the Sixth Framework Programme 2002-2006 Topic(s) MOBILITY-2.1 - Marie Curie Intra-European Fellowships (EIF) Call for proposal FP6-2002-MOBILITY-5 See other projects for this call Funding Scheme EIF - Marie Curie actions-Intra-European Fellowships Coordinator IMPERIAL COLLEGE LONDON EU contribution No data Address Exhibition Road LONDON United Kingdom See on map Total cost No data