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Updated: Jul 4, 2026
15:04
Picometer-Precision Atomic Position Tracking through Electron Microscopy
Published on: July 3, 2021
Atomic-Scale Displacement in Ordered SmMnO3 Nanoislands.
Junyue Han1,2, Yubo Ma1, Ning Chen1
1Medical Science and Technology Innovation Center; and Electron Microscopy Center, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan 250117, China.
Langmuir : the ACS Journal of Surfaces and Colloids
|July 2, 2026
Summary
Epitaxial strain in samarium manganite (SmMnO3) nanoislands influences multiferroicity by altering atomic structures. This study reveals how strain impacts bond angles and lengths, providing insights into structural polar behavior.
Area of Science:
- Materials Science
- Solid-State Physics
- Nanotechnology
Background:
- Multiferroicity in orthorhombic RMnO3 is sensitive to epitaxial strain.
- Strain modulates Mn-O-Mn bond angles and Mn-O bond lengths, affecting magnetic and ferroelectric interactions.
Purpose of the Study:
- To resolve the atomic structure of SmMnO3 nanoislands on SrTiO3.
- To quantify strain gradients and polar displacements at the atomic scale.
- To understand the relationship between structure and polar behavior in SmMnO3.
Main Methods:
- High-angle annular dark-field (HAADF) and annular bright-field (ABF) imaging.
- Atomic-resolution energy-dispersive X-ray spectroscopy (EDS).
- Electron energy loss spectroscopy (EELS).
Main Results:
- Quantified lattice constants, strain gradients, and polar displacements (4.26–20.47 pm).
- Observed Mn-O bond shortening and Mn-O-Mn angle enlargement under in-plane compression.
- Revealed uniform oxygen vacancies and mixed Mn valence states (Mn3+/Mn2+).
Conclusions:
- Atomic-scale strain significantly impacts the structural polar behavior of SmMnO3.
- Strain-induced structural changes are crucial for understanding multiferroicity.
- Findings guide future functional applications of SmMnO3 nanoislands.
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