Visible Modulation of Epsilon Near Zero Materials

While Epsilon-Near-Zero materials have offered many benefits from their introduction to the field of nonlinear optics, those materials have also narrowed the range of wavelengths often studied. With reliable and proven enhancements to light-matter interaction in the ENZ region, many researchers have had little reason to extend the spectrum measured in experiments. The purpose of this work is to measure the intensity dependent refractive index of Indium Tin Oxide across a broad spectral range, from ultraviolet to near infrared, to improve the understanding of semiconductor nonlinearities far from Lorentz and Drude resonances. Furthermore, the visible region is naturally low-loss in Transparent Conducting Oxides, improving the efficiency of nonlinear devices. This is accomplished through an extensive pump-probe experiment referenced to ellipsometer measurements. The resulting data is used to analytical model the resulting change in refractive index throughout the spectrum. A figure of merit is calculated to quantify the benefit of transparency in nonlinear interaction.