Evaluation of the optical axis tilt of Zinc oxide films via noncollinear second harmonic generation

TL;DR

This paper presents a method using noncollinear second harmonic generation to determine the optical axis tilt in Zinc oxide films, providing a non-destructive optical characterization technique.

Contribution

It introduces a novel approach to measure the optical axis tilt in Zinc oxide films through polarization-dependent SHG mapping and analytical modeling.

Findings

Optical axis tilt can be accurately retrieved using SHG polarization maps.

The method effectively characterizes the optical anisotropy of Zinc oxide films.

The approach is non-destructive and applicable to thin film analysis.

Abstract

We investigated noncollinear second harmonic generation form Zinc oxide films, grown on glass substrates by dual ion beam sputtering technique. At a fixed incidence angle, the generated signal is investigated by scanning the polarization state of both fundamental beams. We show that the map of the generated signal as a function of polarization states of both pump beams, together with the analytical curves, allows to retrieve the orientation of the optical axis and, eventually, its angular tilt, with respect to the surface normal