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Charge order pervades the phase diagrams of quantum materials where it competes with superconducting and magnetic phases, hosts electronic phase transitions and topological defects, and couples to the lattice generating intricate structural distortions. Incommensurate charge order is readily stabilized in manganese oxides, where it is associated with anomalous electronic and magnetic properties, but its nanoscale structural inhomogeneity complicates precise characterization and understanding of its relationship with competing phases. Leveraging atomic-resolution variable-temperature cryogenic scanning transmission electron microscopy, we characterize the thermal evolution of charge order as it transforms from its ground state in a model manganite system. We find that mobile networks of discommensurations and dislocations generate phase inhomogeneity and induce global incommensurability in an otherwise lattice-locked modulation. Driving the order to melt at high temperatures, the discommensuration density grows, and regions of order locally decouple from the lattice periodicity. Published by the American Physical Society2025
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This content will become publicly available on September 1, 2025
Bragg coherent diffractive imaging for defects analysis: Principles, applications, and challenges
The ability to visualize crystalline defects and lattice distortions at the nanoscale holds profound implications for enhancing material properties and optimizing their design. Bragg coherent diffractive imaging (BCDI) emerged as a powerful technique due to its simplicity and high sensitivity to lattice strains. This review examines recent advancements in BCDI, highlighting its capability to uncover defects under various experimental conditions. It discusses fundamental principles and data analysis intricacies as well as BCDI's applications in characterizing structural and functional materials. Furthermore, it offers perspectives on the current limitations of BCDI and the potential implications of synchrotron upgrades. By providing these insights, the review aims to enhance the role of BCDI in advancing materials science and nanotechnology.
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- Award ID(s):
- 1944907
- PAR ID:
- 10575973
- Publisher / Repository:
- AIP
- Date Published:
- Journal Name:
- Chemical Physics Reviews
- Volume:
- 5
- Issue:
- 3
- ISSN:
- 2688-4070
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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