Diagnostic results of new-generation dispersive element test samples based on Bragg structures in fused silica

TL;DR

This paper presents diagnostics of new dispersive elements based on Bragg structures in fused silica, highlighting the influence of inscription parameters and demonstrating their potential for high-power radiation compression.

Contribution

It provides a detailed analysis of inscription effects and establishes a threshold intensity for optimal properties of the dispersive elements.

Findings

Threshold inscription intensity is ~6.38 TW/cm2.

Linear absorption remains very low below the threshold.

Dispersion measurements agree with manufacturer calculations.

Abstract

A comprehensive diagnostics of new-generation dispersive elements based on Bragg structures was completed. The influence of inscription parameters on the properties of samples was studied and a threshold inscription intensity of ~ 6.38 TW/cm2 at which the linear absorption coefficient as well as the phase and polarization stresses sharply increase was found. When inscription is made with an average intensity below the threshold, the linear absorption in dry silica samples remains at a level of 10-5 cm-1, which is approximately two orders of magnitude lower than that of currently available commercial samples. The measured values of the dispersion characteristics using a white light interferometer coincided are in a good agreement with the calculated values provided by the manufacturer. The results of the diagnostics show that the new-generation dispersive elements are promising for compressing kilowatt-level radiation of average power.