Room-temperature 2.63 μm GaInAsSb/GaSb strained quantum-well laser diodes

Diode lasers operating at room temperature (23 degrees C) with an emission wavelength of 2.63 mu m have been fabricated from compressively strained Ga0.50In0.50As0.22Sb0.78/GaSb multiple-quantum-well structures grown by molecular beam epitaxy. Ridge waveguide lasers 600 mu m long exhibited an RT current threshold of 500 mA, optical power efficiency of 35 mW A(-1)/facet and a differential quantum efficiency of 14.5%, A pulsed threshold current density less than 2 kA cm(-2) with a characteristic temperature T-0 = 45 K have been achieved for broad mesa devices. The laser structure, which has a type-II band alignment at the well-barrier interface, showed an internal efficiency eta(i) = 33%, controlled by the electron-hole wavefunction overlap at the interface.