Cascaded superlattice InAs/GaSb light-emitting diodes for operation in the long-wave infrared

Abstract

Superlattice InAs/GaSb light-emitting diodes with peak emission wavelength of 8.6 μ and output power approaching 190 μ W at 77 K from a 120 × 120 μ m2 mesa are demonstrated. Output power in excess of 600 μ W dollar; was demonstrated from a 520 × 520 μ m2; mesa at 1 A drive current and 50% duty cycle. Devices were grown by molecular beam epitaxy on lightly n-doped GaSb substrates and employed a 16-stage cascaded active region configuration to improve current efficiency and increase optical output. Emitting regions were coupled by semi-metallic tunnel junctions consisting of a p-GaSb layer and a thickness-graded InAs/GaSb superlattice stack. © 2010 IEEE.