Dynamic nanophotonics and nonlinear optics with oxides and nitrides

Control over the permittivity and relaxation time in materials is important to gain control over the amplitude, phase and polarization of light. In this presentation, we report our work on controlling the static and dynamic optical properties of transition metal nitrides and transparent conducting oxides for a wide array of nanophotonic applications and nonlinear optical demonstrations. We find the carrier relaxation mechanism in titanium and zirconium nitride by pump-probe studies near the ENZ. We demonstrate high-harmonic generation in refractory TiN films. We show large changes in the epsilon-near-zero points in cadmium oxide via yttrium doping, for optically controlled, mid-IR reflectance modulation. In undoped zinc oxide, we demonstrate unity-order permittivity modulation by optical doping, with 20ps response time. With TiN-AZO Berreman-metasurfaces, we demonstrate simultaneous picosecond switching at telecom wavelengths, and nanosecond switching in the visible regime. Employing the ENZ effects in aluminum-doped zinc oxide, we demonstrate nonlinear optical phenomena spanning optical time-reversal to negative refraction. Our work will aid the development of dynamic devices for a wide array of dynamic optical applications.