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Updated: May 30, 2026
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Quantitative Atomic-Site Analysis of Functional Dopants/Point Defects in Crystalline Materials by Electron-Channeling-Enhanced Microanalysis
Published on: May 10, 2021
Structural modulation and hole distribution in Sr(14-x)Ca(x)Cu(24)O(41).
1Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China.
Summary
Structural modulation in Sr(14-x)Ca(x)Cu(24)O(41) compounds is linked to hole distribution. Calcium substitution causes charge redistribution between chains and ladders, impacting structural properties.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Solid-State Chemistry
Background:
- Spin-ladder compounds like Sr(14-x)Ca(x)Cu(24)O(41) exhibit complex electronic and structural properties.
- Understanding hole distribution is crucial for tuning their physical characteristics.
Purpose of the Study:
- To investigate the relationship between structural properties and hole distribution in Sr(14-x)Ca(x)Cu(24)O(41).
- To elucidate the impact of calcium substitution on charge distribution within the compound.
Main Methods:
- Transmission electron microscopy (TEM) for structural analysis.
- Electron diffraction and high-resolution TEM imaging.
- X-ray ionization edge spectroscopy (O K and Cu L(2,3)) to probe electronic states.
- Density functional theory (DFT) calculations for theoretical validation.
Main Results:
- TEM revealed an incommensurate structural modulation along the c-axis due to two mismatched sublattices.
- Hole distribution analysis indicated a higher concentration of doped holes in the chains compared to the ladders.
- Calcium substitution for strontium led to a redistribution of charge between the chain and ladder subsystems.
Conclusions:
- The observed structural modulation is strongly dependent on the hole distribution within the Sr(14-x)Ca(x)Cu(24)O(41) system.
- Charge redistribution induced by Ca substitution significantly influences the interplay between structural and electronic properties.
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