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Updated: Jun 27, 2025
08:55
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
8.5K
Cd-content and temperature dependences of hyperfine fields in CdxFe3-xO4
1Institute of Science and Engineering, Kanazawa University, Kanazawa, Ishikawa 920-1192, Japan.
Summary
Cadmium doping in CdxFe3-xO4 lowers magnetic transition temperature and alters hyperfine fields. These changes are linked to how cadmium ions affect iron spin interactions in the spinel structure.
Area of Science:
- Materials Science
- Solid State Physics
- Magnetism
Background:
- Spinel ferrites like CdxFe3-xO4 are technologically important magnetic materials.
- Understanding the influence of doping on their magnetic properties is crucial for material design.
Purpose of the Study:
- To investigate the effect of cadmium (Cd) content on hyperfine fields and magnetic transition temperature in CdxFe3-xO4.
- To elucidate the role of Cd doping on the magnetic interactions within the spinel structure.
Main Methods:
- Time-differential perturbed angular correlation (TDPAC) spectroscopy using the 111Cd(←111In) probe.
- Systematic variation of Cd content (x) from 0 to 0.5.
- Temperature-dependent measurements of hyperfine fields.
Main Results:
- Cd2+ ions preferentially occupy tetrahedral A sites in the spinel structure.
- Increasing Cd content (x) decreases the magnetic transition temperature (TC) due to lattice expansion and altered Fe spin ordering.
- Room-temperature supertransferred magnetic hyperfine field (SMHF) decreases with increasing x.
- At low temperatures (15 K), SMHF initially increases with x up to x=0.4, then decreases at x=0.46, indicating complex magnetic interactions.
Conclusions:
- Cd doping influences the magnetic properties of CdxFe3-xO4 by affecting lattice constants and Fe spin interactions.
- The observed changes in SMHF are attributed to the impact of Cd doping on antiferromagnetic coupling between Fe ions at A and B sites.
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