Nanocrystal Orientation Analysis of PbSe Quantum Dot 3D Superlattices Enabled By Atomic Lattice Resolved Electron Tomography

Colloidal quantum dot superlattices with semiconductor properties promise many exciting properties for opto-electronic devices including the delocalization of electronic bands with tunable energies. We have applied novel data analysis techniques to HAADF STEM tomographic reconstructions to measure the nanoparticle atomic lattice orientation of each of the 633 quantum dots within a 3D superlattice. Inhomogeneity in position and orientation reveal how surface layers remain more ordered after synthesis and effect interior layering. Current characterization methods like 4D-STEM and GISAXS do not probe the exact the structure of the superlattice in three dimensions. This presentation will highlight the data used and its applications in improving the superlattice structure to achieve next-generation opto-electronic properties.