Multimillion-atom modeling of InAs/GaAs quantum dots: interplay of geometry, quantization, atomicity, strain, and linear and quadratic polarization fields

Role of Quantum Confinement in 10 nm Scale Perovskite Optoelectronics

“…Solid understanding of band energy fluctuations driven by structural and compositional variations can be accelerated with simulation-based studies that can consider realistic conditions of physical samples because they can explore a wide range of supercell geometries and materials that is hard to completely cover with experimental efforts. An atomistic tight-binding (TB) approach, which is well-established to extend the scope of electronic structure simulations to solid structures of physically realizable dimensions that include up to several million atoms, − has been extensively adopted to explain experimentally observed effects of structural and atomic variations on material properties. − Boyer-Richard et al proposed a set of TB parameters that reasonably match a DFT-calculated bulk band structure of methylammonium lead iodide (MAPbI 3 ) near band edges, opening the possibility to use a TB theory for large-scale electronic structure simulations of MHPs. Ashhab et al extended the scope of TB simulations to methylammonium lead bromide (MAPbBr 3 ), where the effects of atomic disorders in mixed halides (MAPbI x Br 3– x ) on band structures are explored for supercells consisting of up to 8 × 8 × 8 cubic unit cells (ucs) (2048 atoms).…”