# Features of photothermal transformation in porous silicon based multilayered structures

## TL;DR

This study investigates photothermal effects in porous silicon multilayer structures by combining theoretical modeling of optical and thermal properties with experimental photoacoustic measurements, enabling accurate thermal conductivity evaluation.

## Contribution

It introduces a comprehensive approach integrating electromagnetic, thermal modeling, and photoacoustic experiments to analyze photothermal transformations in porous silicon multilayers.

## Key findings

- Theoretical models accurately predict temperature profiles within the structure.
- Photoacoustic signals match simulations, validating the thermal analysis method.
- Thermal conductivity can be reliably determined from photoacoustic data.

## Abstract

This paper is devoted to the study of photothermal transformations in multilayered structures. As a modelled sample, porous silicon with a periodic distribution of the porosity was chosen. The spatial distribution of the optical properties inside the structure was evaluated under Brugmann approximation. The heat sources arising as a result of electromagnetic radiation absorption in the structure were estimated by solving Maxwell equations. This allowed us to calculate temperature profiles inside photo-excited sample. For experimental measurements, photoacoustic set-up with a gas-microphone transduction system was chosen to investigate thermal properties of the structure. The results of the photoacoustic response simulation based on the gas-piston model demonstrated an excellent agreement with experiments. This allows a reliable evaluation of the thermal conductivity by fitting the experimental amplitude-frequency photoacoustic signal with the simulated one.

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Source: https://tomesphere.com/paper/1907.02875