Probing Carrier Dynamics of CdTe/ZnCdSe Intermediate Band Solar Cells by Time Resolved Reflection*

Intermediate band photovoltaic have the potential to overcome the Shockley Queisser limit and potentially can achieve efficiencies as high 63%.  In this work we present time resolved reflectance measurements of intermediate band solar cells made from CdTe fractional monolayer QDs embedded in a ZnCdSe host matrix. The solar cells are grown by molecular beam epitaxy. An intermediate band is formed by incorporating CdTe fractional monolayer QDs embedded in a ZnCdSe host matrix. The type-II band alignment and the lack of a wetting layer make these materials very suitable for IB-devices. A superlattice structure of CdTe/ZnCdSe QDs (100 periods) is presented in which the size and the strain of the QDs are analyzed by X-ray diffraction and is analyzed spectroscopically.