Nanoscale imaging of the full strain tensor of specific dislocations extracted from a bulk sample

Journal article

Lattice defects play a key role in determining the properties of crystalline materials. Probing the three-dimensional (3D) lattice strains that govern their interactions remains a challenge. Bragg coherent diffraction imaging (BCDI) allows strain to be measured with nanoscale 3D resolution. However, it is currently limited to materials that form microcrystals. Here we introduce a technique that allows the manufacture of BCDI samples from bulk materials. Using tungsten as an example, we show that focused ion-beam machining can be used to extract, from macroscopic crystals, micron-sized BCDI samples containing specific preselected defects. To interpret the experimental data, we develop a displacement-gradient-based analysis for multireflection BCDI. This allows accurate recovery of the full lattice strain tensor from samples containing multiple dislocations. These capabilities open the door to BCDI as a microscopy tool for studying complex real-world materials.

Authors: Hofmann, F; Phillips, N; Das, S; Karamched, P; Hughes, G

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: American Physical Society
• Journal: Physical Review Materials
• Volume: 4
• Issue: 1
• Article number: 013801
• Publication date: 2020-01-14
• Acceptance date: 2019-10-17
• DOI: 10.1103/PhysRevMaterials.4.013801
• EISSN: 2475-9953
• Language: English
• Keywords: FFR