Long-wavelength IR interband cascade light emitting diodes

Electroluminescence in the long-wavelength (6-8 mu m) spectrum region is observed from Sb-based type-II interband cascade quantum well structures. The device structures were grown by molecular beam epitaxy on GaSb substrates and comprises many (15 for the first sample and 12 for the second sample) repeated periods of active regions separated by digitally graded multilayer injection regions. The devices have been operated at 300 K and 77 K with an output optical power up to 700 nW. The strong blue shift of the electroluminescent peak with the applied bias due to the Stark effect has also been observed.