Tight-binding theory of the excitonic states in colloidal InSb nanostructures

Abstract

This study achieves atomistic calculations of both InSb nanocrystals (NCs) and nanorods (NRs) which are important members of the III−V semiconductor family. A more accurate model of tight-binding theory together with an applicable configuration interaction is utilized for such purposes. The discovered comparisons demonstrate that the excitonic energies calculated using tight-binding theory are more consistent with experimental results rather than others computed by the eight-band Pidgeon and Brown model within zinc-blende and wurtzite structure. In addition, detailed predictions of single-particle gaps and excitonic gaps for InSb nanorods as a function of length-to-diameter ratios are theoretically observed. When aspect ratios are increased, a reduction of single-particle gaps and excitonic gaps is duly presented because of the resulting quantum confinement. The electron and its associated hole are more confined within zinc-blende than containment in wurtzite nanostructures owing to coulomb interaction. Finally, an analysis of InSb nanostructures can provide useful guidelines for the designs required for electronic and optical properties pertaining to near-infrared active III-V semiconductor nanostructures.