In(Ga)As/GaAs(001) quantum dot molecules probed by nanofocus high resolution x-ray diffraction with 100 nm resolution

摘要

In(Ga)As quantum dots, which laterally self-assemble into quantum dot molecules, have been studied by scanning x-ray nanodiffraction, finite element calculations and subsequent kinematical diffraction simulations. X-ray beam sizes of 100 nm enable small scattering volumes comparable to the object size at extremely high local flux densities (=10~4 photons nm~(-2) s~(-1))- By that bulk contributions to the scattering are effectively reduced. Area maps of various individual quantum dot molecules have been measured, whereas the diffraction patterns therein reveal spatially resolved information about the inter quantum dot position correlation function.