Atomistic tight-binding computations in electronic structures and optical signatures of wurtzite structured InAs and InP nanocrystals

Abstract

III-V nanocrystals with wurtzite phase demonstrate the unique anisotropic nature for the light extraction applications in optoelectronic devices; this is analyzed by the atomistic tight-binding theory. The electronic and optical signatures of wurtzite structured InAs and InP nanocrystals are determined and compared with experimental data. The physical characteristics are sensitive with nanocrystal materials and sizes. Credited by the quantum confinement, the size-dependent optical band gaps are quantitatively demonstrated. The optical spectra ranging from ultraviolet to infrared wave length are extensively tuned by changing the nanocrystal materials and diameters. The optical band gaps of the tight-binding model agree well with the experimental work. The optical signatures of InP nanocrystals are better than those of InAs nanocrystals. The electron-hole pairs are easily generated with the growing diameters. The stokes shifts are initially reduced and then are supposed to be unchanged by the growing diameters.