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Room Temperature Magnetic Memory Effect in Nanodiamond/γ-Fe2O3 Composites
Ashish Chhaganlal Gandhi1, Rajakar Selvam1, Chia-Liang Cheng1
1Department of Physics, National Dong Hwa University, Hualien 97401, Taiwan.
Nanomaterials (Basel, Switzerland)
|April 3, 2021
Summary
We discovered a room temperature magnetic memory effect in magnetic nanodiamond (MND) composites. This effect, observed in nanodiamond/γ-Fe2O3, shows potential for spintronic applications.
Area of Science:
- Materials Science
- Nanotechnology
- Condensed Matter Physics
Background:
- Magnetic nanodiamond (MND) composites offer novel functionalities.
- Understanding magnetic properties at room temperature is crucial for advanced applications.
Purpose of the Study:
- To investigate the room temperature magnetic memory effect (RT-MME) in magnetic nanodiamond (ND)/γ-Fe2O3 nanocomposites.
- To analyze the structural and magnetic properties of these nanocomposites.
Main Methods:
- Synchrotron radiation X-ray diffraction for crystal structure analysis.
- DC SQUID magnetometry for magnetic measurements.
- Temperature, field, and time relaxation protocols to study magnetic memory.
Main Results:
- MND composites consist of 99% ND and 1% γ-Fe2O3 phases.
- γ-Fe2O3 nanoparticles exhibit non-interacting superparamagnetic behavior with a wide blocking temperature distribution.
- A significant magnetic memory effect was observed at room temperature.
Conclusions:
- The magnetic dynamics of MND are influenced by a broad distribution of γ-Fe2O3 nanoparticle sizes and relaxation times.
- The observed room temperature ferromagnetism and MME suggest potential applications in nanodiamond-based spintronics.
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