Electron hole interactions in GaSb/InAs type-II superlattices

Band to band excitation at depletion region is used to detect the infrared light in InAs/GaSb superlattice structures. In this system electrons and holes are spatially separated in the carrier states of InAs and GaSb layers respectively. For this reason electron hole wavefunction overlap is weak at interface. With applied reverse bias overlap can be increased. In this way Auger Recombination process which reduces the detectivity is supressedIn this thesis we present the theoretical investigation of electron hole interaction in InAs/GaSb Type II superlattices. Kronig-Penney model and Envelope function approximation (EFA) is used to calculate band gap energy and superlattice minibands. Built-in voltage and Fermi energies are calculated for p-n junction formed by n-doped InAs and p- doped GaSb. Variational method is also used to calculate exciton binding energies. Also applied voltage dependence of the number of superlattice period, width the depletion region and built-in voltage are investigated.