AlGaAs-on sapphire nanowaveguide with high FOM for coherent two octave spanning supercontinuum generation using low peak power

In this paper, a nano-engineered AlGaAs-on insulator rib waveguide is designed and numerically analysed for coherent supercontinuum generation at low peak power. AlGaAs, also known as the ‘silicon of non-linear optics’, is an excellent candidate for integrated non-linear platforms and is utilized as the core material. The dispersion-engineered, optimized design structure offers two zero-dispersion wavelengths (ZDWs), near 2 and 3.9 µm. Our simulation results show that the coherent SC spectra broaden from 1.15 to 5 µm (two octaves at −40 dB) in a 1 mm-long waveguide when pumped with 2.5-µm secant hyperbolic pulses, having a pulse width of 100 fs and a peak power of 166 W. Its high figure of merit (almost two degrees of magnitude greater), along with a high degree of coherence, makes it a highly suitable structure for power-efficient and advanced future non-linear integrated platforms.