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Room-temperature ferromagnetic Cr-doped Ge/GeOx core-shell nanowires
Amar S Katkar1, Shobhnath P Gupta2, Md Motin Seikh3
1Dr. B N Purandare Arts and Smt. S G Gupta Commerce and Science College, Valvan, Lonavla, Pune-410403, India.
Nanotechnology
|March 20, 2018
Summary
Chromium-doped germanium/germanium oxide core-shell nanowires exhibit room-temperature ferromagnetism. Their magnetic properties, sensitive to shell thickness, show potential for spintronic devices.
Area of Science:
- Materials Science
- Nanotechnology
- Condensed Matter Physics
Background:
- Dilute magnetic semiconductors are crucial for spintronic applications.
- Germanium-based nanomaterials offer unique electronic and magnetic properties.
- Controlling magnetism in nanomaterials requires precise structural engineering.
Purpose of the Study:
- To synthesize and characterize chromium-doped germanium/germanium oxide core-shell nanowires.
- To investigate the influence of core-shell structure and thickness on magnetic properties.
- To explore the potential of these nanowires for spintronic devices.
Main Methods:
- Synthesis of Cr-doped Ge/GeOx core-shell nanowires.
- Characterization using X-ray diffraction, electron microscopy (SEM, TEM), and spectroscopy (EDS, XPS).
- Magnetization studies to determine magnetic properties and Curie temperature.
Main Results:
- Tunable shell thickness achieved by varying synthesis temperature.
- Confirmation of metallic Cr and Cr3+ in the core-shell structure.
- Room-temperature ferromagnetism observed, highly dependent on shell thickness.
- High Curie temperature (TC > 300 K) with significant magnetic remanence (MR) and coercivity (HC).
Conclusions:
- Cr-doped Ge/GeOx core-shell nanowires exhibit robust room-temperature ferromagnetism.
- The core-shell structure is essential for achieving ferromagnetism in these materials.
- These nanowires show promise as hard magnets for advanced spintronic applications.
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