Reference free Chi 3 dispersion measurements in planar tantalum pentoxide waveguides

摘要

We utilize analysis of third harmonic generation under femtosecond pulsed excitation as a reference free measurement method for third order nonlinear susceptibility (χ~((3)) or "Chi 3") of planar waveguides. We investigate χ~((3)) dispersion in planar Ta_2O_5 waveguides at wavelengths either side of the telecoms window, obtaining a nonlinear coefficient ofrn2 × 10~(-13) esu, at 1550 nm. Our study indicates that χ~((3)) increases within the measured wavelength range due to a three-photon resonance of Ta_2O_5 electrons, revealing the potential of this material system in high speed integrated nonlinear optical switches for the telecommunications spectral window.