Multi-band simulation of quantum transport in resonant interband tunneling devices

We have analyzed quantum transport in InAs/AlSb/GaSb/AlSb/InAs (type II) double-barrier resonant interband tunneling diodes. Our procedure uses a tight-binding non-equilibrium Greenʹs function method where an evanescent wave matching at heterointerfaces as well as a realistic band structure, i.e., the conduction-valence-band-mixing effects are duly taken into account. We have compared our results with experimental results and those of a two-band model which considers only the lowest conduction and the light-hole states. Our results show that current–voltage characteristics have extra current due to the significant heavy-hole mixing effects in the GaSb quantum well especially when the well width (Lw) is less than 12 mono layers. It should be noted that the matching of evanescent electron modes is essentially necessary to include the valley-mixing effects for the heterostructures, since breaking of a lattice-translational symmetry occurs at the interfaces.