Absorption profile of laser impulse of composites based on transparent matrix and metal nanoparticles

Abstract

In this work the technique of modeling of optoacoustic signal initiated by laser pulse in composites based on transparent matrix and metal nanoparticles was proposed. It was shown that the time to achieve mechanical equilibrium is significantly lower than the pulse duration, and pressure is proportional to the augmentation of the nanoparticles? temperature. Testing of the modeling technique was carried out on the example of PETN - aluminum nanoparticles composite in two variant with and without taking into account the temperature dependence of the composites? optical properties. Comparison of calculated and experimental dependences of the effective absorption coefficient on the energy density of neodymium laser with pulse duration 14 ns was made. The modeling results are in good agreement with the experimental data only if the temperature dependence of the optical properties is taken into account.