Optoelectronic devices based on type II polytype tunnel heterostructures

Abstract

We describe a new family of optoelectronic devices based on the unique properties of combinations of semiconductor tunnel junctions with type II polytype heterostructures. A typical light-emitting device structure consists of AlSb (thin barrier)/InAs(quantum well)/AlSb(thin barrier) structure clad by AlInAsSb emitter and GaSb collector. The emission source is the intersubband radiative transition between the first two subbands in the InAs well. Since the conduction-bank minimum of InAs is energetically lower than the valence-band maximum of GaSb, the device can be designed in such a way that electrons are injected only into the higher subband and extracted out only from the lower subband, both via tunneling, leading to an intraband population inversion and highly efficient radiative transitions. The same operation principle can be applied to design detector structures.