780 nm oxidised vertical-cavity surface-emitting lasers with Al0.11Ga0.89As quantum wells

Low threshold vertical-cavity surface-emitting lasers with Al_0.11Ga_0.89As four quantum wells for 780 nm wavelength emission are fabricated using aluminum oxide apertures. The fabrication process requires only single step mask alignment. The 3.4 μm square laser exhibits a low threshold current of 200 μA, which is more than an order of magnitude smaller than the previous values obtained at 780 nm. Singlemode peak output power is 1.1 mW. This 3.4 μm laser is found to operate in the fundamental transverse mode over the complete operating current range. The 7.6 μm square laser shows peak output power of 2.7 mW