Experiment verification of second harmonic generation from ENZ material

Abstract

Epsilon near zero (ENZ) material is a material with near zero permittivity and it has drawn considerable attention in light-matter interaction. One of the unique features is it allows the electromagnetic wave to squeeze and tunnel through a narrow ENZ channel. In this experiment, we look into the nonlinear generation of the two-dimension (2D) ENZ structure in second order susceptibility which can achieve ENZ at normalise frequency of 2. We also observe the tunability and enhancement of the second harmonic generation (SHG) intensity when the incident wave excited at different wavelengths of mid-infrared in ENZ condition. Our study proved that shorter wavelength can obtain better enhancement.