Piezooptic Properties of beta-BaB2O4 and Li2B4O7 Crystals

TL;DR

This study calculates the photoelastic coefficients and estimates the acoustooptic figure of merit for beta-BaB2O4 and Li2B4O7 crystals, providing insights into their potential for acoustooptic applications.

Contribution

It presents the first calculation of photoelastic coefficients and estimation of acoustooptic figure of merit for these specific crystals based on experimental measurements.

Findings

AO figure of merit for beta-BaB2O4 reaches 243.4×10^-15 s^3/kg

AO figure of merit for Li2B4O7 reaches 2.57×10^-15 s^3/kg

Propagation directions of acoustic waves are identified

Abstract

Photoelastic coefficients of beta-BaB2O4 and Li2B4O7 crystals are calculated on the basis of piezooptic measurements performed with interferometric technique and the elastic compliance and stiffness data. Using the experimental results, the acoustooptic (AO) figure of merit (FM) has been estimated for the possible geometries of AO interaction. It is shown that the AO FM for the ABO and LTB crystals reach respectively the values M2=243.4*10-15s3/kg and M2=2.57*10-15s3/kg, if the interaction with the slowest ultrasonic waves (v=933.5m/s and v=3173m/s) is concerned. The directions of propagation and polarization of those acoustic waves are obtained on the basis of construction of indicative surfaces of the acoustic wave velocities.