Intersubband absorption saturation in AlN-based waveguide with GaN/AlN multiple quantum wells grown by metalorganic vapor phase epitaxy

Intersubband absorption saturation at 1.57 mu m wavelength was observed in a 400-mu m long Si(3)N(4)-rib AlN-based waveguide with GaN/AlN multiple quantum wells (MQWs) fabricated by metalorganic vapor phase epitaxy (MOVPE). The self-saturation measurement was employed using a 1.56-mu m short pulse laser which has a temporal width of 0.4 ps (full-width at half-maximum) and a repetition rate of 63 MHz. An intersubband absorption saturation by 5 dB was achieved using a pulse energy of 115 pJ. We have demonstrated the capability of MOVPE-grown GaN/AlN MQWs for intersubband optical devices operated at communication wavelength. (C) 2011 American Institute of Physics. [doi:10.1063/1.3650929]