Theoretical performance of very long wavelength InAs/InxGa1−xSb superlattice based infrared detectors

Optimal detectivities of very long wavelength (11–19 μm) photovoltaic infrared detectors based on ideal InAs/InGaSb superlattices are calculated. Accurate K⋅p band structures are used to obtain radiative, electron–electron and hole–hole band-to-band Auger, and for the first time shallow acceptor level assisted Auger recombination rates for n-on-p photodiodes. The suppression of band-to-band Auger by ‘‘band gap engineering’’ is predicted to lead to improved background-limited operating temperatures just as it does in long-wave InAs/InGaSb infrared detectors.