Visualization Techniques for Assessing Inhomogeneities and Stress in Ti:Sapphire

TL;DR

This paper introduces two innovative optical measurement techniques for detailed visualization of inhomogeneities and stress in Ti:Sapphire crystals, enhancing material characterization for optical applications.

Contribution

The study presents novel measurement methods for precise optical property mapping and stress detection in Ti:Sapphire, including the first visualization of a new central optical pattern.

Findings

High-resolution optical property maps of Ti:Sa samples

Identification of stress and inhomogeneities using circular polarization

Discovery of a new central optical pattern likely from crystal growth

Abstract

This study presents a comprehensive optical analysis of titanium-doped sapphire (Ti:Sa) crystals, introducing two innovative measurement techniques to enhance the characterization of this material. The first method enables highly precise transmission measurements, facilitating the visualization of optical doping patterns across samples and providing accurate Figure of Merit (FoM) evaluations. This technique covers an area of 25 x 100 mm, allowing for the creation of detailed optical property maps. The second method is specifically designed to identify stress and refractive index inhomogeneities using circular polarization, leveraging the birefringent properties of Ti:Sa material. Experimental validation was performed on three Ti:Sa samples with distinct defects, analyzing and comparing their optical and structural properties. A novel central optical pattern, previously unreported, was observed in all samples. This pattern is hypothesized to originate from core formation during crystal growth. These findings provide new insights into the material's internal structure and hold significant implications for its optimization in optical applications.