Predan, FelixFelixPredanFranke, A.A.FrankeHöhn, OliverOliverHöhnLackner, DavidDavidLacknerHelmers, HenningHenningHelmersSiefer, GeraldGeraldSieferBett, Andreas W.Andreas W.BettDimroth, FrankFrankDimroth2022-03-152022-03-152020https://publica.fraunhofer.de/handle/publica/41249510.1109/PVSC45281.2020.9300633III-V based multi-junction solar cells with 4 to 6 junctions reach the highest efficiencies for the conversion of solar energy today. We present the latest results on the development of a GaInP/GaAs/GaInAs//GaSb four-junction solar cell. The implemented devices show an efficiency of 43.8 ±2.6 % at a concentration of 796 suns and the efficiency decreases only marginally for higher concentrations up to 1378 suns. The remaining loss mechanisms of the device are analyzed and quantified. The Sb-based four-junction cell has the potential of reaching 50% conversion efficiency in future.en621697conference paper