Electronic structure and optical properties of colloidal InAs/InP core/shell nanocrystals: Tight-binding calculations

Using a combination of atomistic tight-binding and valence force field model, the relative impact of quantum confinement and strain field on structural and optical properties in InAs/InP core/shell nanocrystals within a constant volume is systematically elucidated and quantified as a function of the aspect ratios (σ) (Rcore/Rshell). The sensitivity of the structural optimization and aspect ratios (σ) with the single-particle spectra, single-particle gaps, excitonic gaps, and ground e-h overlaps is successfully realized. Good agreement with experimental results is presented. These calculations provide an understanding of the interplay between structural characteristics and changes in electronic properties. Finally, a study of the desired InAs/InP core/shell nanocrystal provides a theoretical basis for tuning the spectral range to cover the novel applications.