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Sub-nanometer-scale mapping of crystal orientation and depth-dependent structure of dislocation cores in SrTiO₃.

ABSTRACT: Defects in crystals play a fundamental role in modulating mechanical, electrical, luminescent, and magnetic behaviors of materials. However, accurate measurement of defect structures is hindered by symmetry breaking and the corresponding complex modifications in atomic configuration and/or crystal tilt at the defects. Here, we report the deep-sub-angstrom resolution imaging of dislocation cores via multislice electron ptychography with adaptive propagator, which allows sub-nanometer scale mapping of crystal tilt in the vicinity of dislocation cores and simultaneous recovery of depth-dependent atomic structure of dislocations. The realization of deep-sub-angstrom resolution and depth-dependent imaging of defects shows great potential in revealing microstructures and properties of real materials and devices.

SUBMITTER: Sha H

PROVIDER: S-EPMC9834382 | biostudies-literature | 2023 Jan

REPOSITORIES: biostudies-literature

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Sub-nanometer-scale mapping of crystal orientation and depth-dependent structure of dislocation cores in SrTiO3.

Sha Haozhi H Ma Yunpeng Y Cao Guoping G Cui Jizhe J Yang Wenfeng W Li Qian Q Yu Rong R

Nature communications 20230111 1

Defects in crystals play a fundamental role in modulating mechanical, electrical, luminescent, and magnetic behaviors of materials. However, accurate measurement of defect structures is hindered by symmetry breaking and the corresponding complex modifications in atomic configuration and/or crystal tilt at the defects. Here, we report the deep-sub-angstrom resolution imaging of dislocation cores via multislice electron ptychography with adaptive propagator, which allows sub-nanometer scale mappin ...[more]

PMID: 36631462

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