Ge-rich SiGe waveguides for supercontinuum generation in the mid-IR

The third-order nonlinear parameter of Ge-rich SiGe waveguides are experimentally retrieved using a bi-directional top hat D-scan at λ = 1.58 μm. The obtained values are then used to fit the theoretical equation, providing promising values in the mid-IR, where the nonlinear effects are no longer limited by two-photon absorption. New Ge-rich SiGe waveguide designs are provided to exploit the nonlinear properties in the mid-IR, showing a flat anomalous dispersion over one octave spanning from λ = 3 µm to λ = 8 μm and a γ parameter that decreases from γ = 10 W -1 m -1 .