Spatially resolved nanodiffraction of quantum dot based solar cells: The role of Sb in the capping layer

This proposal aims to investigate InAs/GaAs quantum dots (QDs) capped with GaAsSb for high-efficiency photovoltaic applications. Our objective is to study the influence of the Sb content (present in the capping layer), owing its key role to the energy band alignment, wavefunction topology and improved efficiency. Thus, this proposal envisages the use of scanning X-ray diffraction microscopy (SXDM) to obtain information about the structural lattice distortions present in QD-devices of different Sb contents. We also intend to record spatially resolved lattice features around the QD- areas by SXDM using an in-operando approach (bias voltage) at the ID01 beamline. Our findings will reveal the effect of high Sb content on the structure, gaining a deeper understanding of the efficiency improvement, and will help to optimize solar cells performance in the future.