Dual-band unipolar barrier infrared photodetector based on InGaAsSb bulk and type-II InAs/GaSb superlattice absorbers

•An InGaAsSb/AlGaSb/T2SL nBn detector structure was epitaxially grown and characterized.•A high crystal quality of InGaAsSb and T2SL absorbers with different bandgaps was achieved.•A dual-band SWIR/MWIR detection was enabled by switching the applied bias polarity.•High detectivities were obtained in both SWIR and MWIR spectral ranges at 77 K.