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Aerosol-assisted Chemical Vapor Deposition of Metal Oxide Structures: Zinc Oxide Rods
Published on: September 14, 2017
Ferromagnetism in carbon-doped zinc oxide systems
B J Nagare1, Sajeev Chacko, D G Kanhere
1Department of Physics, University of Mumbai, Santacruz (East), Mumbai 400 098, India. bjnagare@physics.mu.ac.in
The Journal of Physical Chemistry. A
|February 4, 2010
Summary
Doping zinc oxide (ZnO) with carbon impurities induces a magnetic moment. Two carbon atoms in ZnO exhibit ferromagnetic interactions, influenced by the material's structure and dimensionality.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Computational Chemistry
Background:
- Zinc oxide (ZnO) is a wide-bandgap semiconductor with diverse applications.
- Investigating magnetic properties in semiconductor materials is crucial for spintronics.
- Doping is a common method to tune the electronic and magnetic properties of ZnO.
Purpose of the Study:
- To investigate the ferromagnetic properties of carbon-doped ZnO clusters and bulk.
- To understand the mechanism and conditions for induced magnetism in ZnO.
- To analyze the role of carbon impurity concentration and structural dimensionality on magnetic interactions.
Main Methods:
- Spin-polarized density functional theory (DFT) calculations.
- Analysis of electronic structure: eigenvalue spectra, spin densities, and molecular orbitals.
- Systematic study of various ZnO cluster sizes and bulk ZnO with substitutional carbon.
Main Results:
- Substitutional carbon doping induces a magnetic moment of approximately 2 Bohr magnetons (μB) in all studied ZnO systems.
- Ferromagnetic interaction is observed in systems with two carbon impurities, with exceptions when impurities share a nearest-neighbor zinc atom.
- Ferromagnetism is mediated by pi-bonds in ring structures and pi- and sigma-bonds in 3D structures.
- The ferromagnetic interaction is significantly enhanced in bulk ZnO compared to clusters, highlighting the role of dimensionality.
Conclusions:
- Carbon doping is an effective route to induce ferromagnetism in ZnO.
- The dimensionality of the ZnO network plays a critical role in mediating and enhancing ferromagnetic interactions between dopants.
- These findings offer insights into designing magnetic semiconductor materials for potential spintronic applications.
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