Long-wavelength infrared (~10-15 mm) electroluminescence from Sb-based interband cascade devices

Electroluminescence in the long-wavelength infrared (10-15 mm) spectrum region was observed from Sb-based type-II interband cascade quantum well structures. The device structure was grown by molecular beam epitaxy on a GaSb substrate and comprises 10 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 50 nW. The emission wavelength, the longest observed in any compound semiconductor material at room temperature, results from tailoring the heterostructure, demonstrating a unique capability of this Sb-family type-II material system.