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Room Temperature Magnetic Memory Effect in Cluster-Glassy Fe-doped NiO Nanoparticles
Ashish Chhaganlal Gandhi1, Tai-Yue Li1, B Vijaya Kumar2
1Department of Physics, National Dong Hwa University, Hualien 97401, Taiwan.
Nanomaterials (Basel, Switzerland)
|July 9, 2020
Summary
Iron-doped nickel oxide (NiO) nanoparticles exhibit enhanced room-temperature ferromagnetism. This discovery is promising for developing new spintronic devices and understanding magnetic materials.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Nickel oxide (NiO) is typically an antiferromagnetic material.
- Room-temperature ferromagnetism in oxides is highly sought after for spintronic applications.
- Doping is a common strategy to modify the magnetic properties of oxide materials.
Purpose of the Study:
- To synthesize and characterize iron (Fe)-doped NiO nanoparticles.
- To investigate the magnetic properties of Fe-doped NiO nanoparticles at room temperature.
- To understand the underlying mechanisms responsible for the observed magnetic behavior.
Main Methods:
- Co-precipitation method for nanoparticle synthesis.
- Magnetic measurements (temperature, time, and field-dependent magnetization).
- Neutron powder diffraction for structural and magnetic analysis.
Main Results:
- Fe-doped NiO nanoparticles display enhanced room-temperature ferromagnetic properties.
- Neutron diffraction indicates an increased magnetic moment of 3d ions with increasing Fe concentration.
- Fe-doping enhances intraparticle interactions via defect clusters, creating magnetic anisotropy energy barriers.
Conclusions:
- Fe-doping induces room-temperature ferromagnetism in NiO nanoparticles.
- The observed ferromagnetism is linked to enhanced intraparticle interactions and defect clusters.
- These findings support the development of room-temperature ferromagnetic oxide systems for spintronics.
Keywords:
4:1 defect clusterFe-doped NiOintraparticle interactionsmagnetic memory effectroom temperatureMore Related Videos
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