Enhanced 3 rd order optical nonlinearity in silicon nitride nanowires
integrated with 2D graphene oxide films
Abstract
numbers of GO layers and at different pump powers. By optimizing the
trade-off between the nonlinearity and loss, we obtain a significant
improvement in the FWM conversion efficiency of ≈7.3 dB for a uniformly
coated device with 1 layer of GO and ≈9.1 dB for a patterned device with
5 layers of GO. We also obtain a significant increase in FWM bandwidth
for the patterned devices. A detailed analysis of the influence of
pattern length and position on the FWM performance is performed. Based
on the FWM measurements, the dependence of GO’s third-order nonlinearity
on layer number and pump power is also extracted, revealing interesting
physical insights about the 2D layered GO films. Finally, we obtain an
enhancement in the effective nonlinear parameter of the hybrid
waveguides by over a factor of 100. These results verify the enhanced
nonlinear optical performance of SiN waveguides achievable by
incorporating 2D layered GO films.