# Transient grating spectroscopy: An ultrarapid, nondestructive materials evaluation technique

## TL;DR

Transient grating spectroscopy (TGS) is a rapid, non-destructive technique that uses laser-induced diffraction gratings to probe material properties like elasticity and thermal diffusivity across various length scales, aiding materials science research.

## Contribution

This paper reviews the application of TGS in non-destructive materials characterization, highlighting its ability to measure multiple properties on sub-microsecond timescales and its potential for in situ analysis.

## Key findings

- TGS can non-destructively measure elasticity, thermal diffusivity, and energy dissipation.
- TGS has been successfully applied to analyze radiation damage, colloidal crystals, and nanostructured systems.
- The technique shows promise for in situ monitoring of dynamic material evolution.

## Abstract

Structure-property relationships are the foundation of materials science. Linking microstructure and material properties is essential for predicting material response to driving forces, managing in-service material degradation, and engineering materials for optimal performance. Elastic, thermal, and acoustic properties provide a convenient gateway to directly or indirectly probe material structure across multiple length scales. We review how using the laser-induced transient grating spectroscopy (TGS) technique, which uses a transient diffraction grating to generate surface acoustic waves (SAWs) and temperature gratings on a material surface, non-destructively reveals the material elasticity, thermal diffusivity, and energy dissipation on the sub-microsecond timescale, within a tunable sub-surface depth. This technique has already been applied to many challenging problems in materials characterization, from analysis of radiation damage, to colloidal crystals, to phonon-mediated thermal transport in nanostructured systems, to crystal orientation and lattice parameter determination. Examples of these applications, as well as inferring aspects of microstructural evolution, illustrate the wide potential reach of TGS to solve old materials challenges, and to uncover new science. We conclude by looking ahead at the tremendous potential of TGS for materials discovery and optimization when applied in situ to dynamically evolving systems.

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Source: https://tomesphere.com/paper/1908.02051