Heterostructure solar cells

Heterostructure solar cells based on III–V compounds are studied. Record-high efficiencies are obtained for solar cells based on AlGaAs/GaAs heterostructures: 24.6% for 100-fold concentration of sunlight in outer space (AM0) and 27.5% for 100-fold concentration of the light on the ground (AM1.5). A substantial increase in radiation resistance is obtained for solar cells with a built-in Bragg mirror. Cascaded solar cells with efficiencies of up to 32% for 100 suns (AM1.5) are created and studied; in these cells the upper wide-gap materials are infrared transparent elements based on GaAs, while the lower narrow-band elements are made of GaSb or an InGaAs solid solution.