Three-dimensional imaging of dislocation propagation during crystal growth and dissolution

Abstract

Atomic level defects such as dislocations play key roles in determining the macroscopic properties of crystalline materials ^{1, 2} . Their effects range from increased chemical reactivity ^{3, 4} to enhanced mechanical properties ^{5, 6} . Dislocations have been widely studied using traditional techniques such as X-ray diffraction and optical imaging. Recent advances have enabled atomic force microscopy to study single dislocations ⁷ in two-dimensions (2D), while transmission electron microscopy (TEM) can now visualise strain fields in three-dimensions (3D) with near atomic resolution ^{8– 10} . However, these techniques cannot offer 3D imaging of the formation or movement of dislocations during dynamic processes. Here, we describe how Bragg Coherent Diffraction Imaging (BCDI) ^{11, 12} can be used to visualize in 3D, the entire network of dislocations present within an individual calcite crystal during repeated growth and dissolution cycles. These investigations demonstrate the potential of BCDI for studying the mechanisms underlying the response of crystalline materials to external stimuli.