High-Pressure Elasticity Tensor from Thermal Diffuse Scattering

TL;DR

This paper introduces a method to determine the full elasticity tensor of materials under high pressure using thermal diffuse x-ray scattering, enabling simultaneous measurement of elasticity and structure from a single experiment.

Contribution

It demonstrates that the elasticity tensor can be extracted from thermal diffuse scattering data of single crystals at high pressures, advancing high-pressure material characterization.

Findings

Elastic constants can be obtained from small crystals of arbitrary symmetry.

Method applicable up to 28 GPa pressure.

Enables study of planetary interior conditions and phase transitions.

Abstract

We report on the determination of high-pressure elasticity from thermal diffuse x-ray scattering of magnesium oxide at pressures up to 28 GPa. We find that the full elasticity tensor as a function of pressure can be extracted from x-ray scattering of single crystals. This enables the simultaneous measurement of elasticity and crystal structure from a single experiment and thus marks a decisive step towards establishing reliable calibration for extreme pressures. Elastic constants can be extracted with this method from small crystals of arbitrary symmetry, shape and optical properties and will allow for significant progress in our understanding of the elastic behaviour of planets interior at geophysically relevant conditions, structural phase transitions and fundamental interactions of phonons with other quasi-particles.