Direct imaging of stress tensor around single dislocation in diamond

TL;DR

This study successfully visualized and measured the stress tensor around a single dislocation in diamond using quantum sensors, confirming elasticity theory predictions and advancing experimental capabilities in defect characterization.

Contribution

It presents the first direct experimental visualization of the stress tensor around a dislocation in diamond using NV center quantum sensors, validating theoretical models.

Findings

Stress tensor components measured around a dislocation match elasticity theory predictions.

Quantum sensors enabled mapping of shear and trace stress components.

Experimental validation of long-standing theoretical models in crystal defect physics.

Abstract

Dislocations are fundamental crystal defects whose stress fields govern a wide range of material properties. The analytical form of the stress tensor around single dislocation was established by elasticity theory more than 80 years ago and has provided a theoretical basis for evaluating essential characteristics of dislocations. However, direct experimental verification has long remained out of reach because it has been difficult to measure the components of the stress tensor with conventional methods. Here, we present the experimental visualization of the stress tensor around single dislocation in diamond. Using quantum sensors based on nitrogen-vacancy (NV) centers, we mapped the shear components ($\sigma_{xy}$, $\sigma_{yz}$, $\sigma_{zx}$) together with the trace of the stress tensor ($\sigma_{xx}+\sigma_{yy}+\sigma_{zz}$) around single 45{\deg} dislocation. The observed distributions exhibited good agreement with predictions from elasticity theory, thus providing experimental validation of this theoretical framework.