The detailed analysis of wavefunction overlaps for InAs/AlSb/GaSb based N-structure type-II SL pin photodetectors

Abstract

We report on a detailed analysis of electron and hole wave functions with their overlap integrals for InAs/AlSb/GaSb based N-structure type-II superlattice (T2SL) pin detectors under applied reverse bias. Bandgap energies and superlattice minibands are performed by envelope function approximation using pseudopotential method for input parameters such as effective masses and envelope functions at Gamma point. The layer thickness of detector structure is designed to operate in the long wavelength infrared range given with the maximum overlap of around 8.6 mu m. Electron wave functions show strong localizations in the neighboring wells under low electrical fields resulting with lower overlap integrals. An increase in the electrical field causes strong overlap by reduced localizations.