Magnetic performance of orthorhombic Mn35Ge35Te30 nanocrystals
| Autor: | Iman A. Mahdy |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
010302 applied physics
Materials science Magnetic domain Magnetic moment Condensed matter physics 02 engineering and technology Coercivity 021001 nanoscience & nanotechnology Condensed Matter Physics 01 natural sciences Electronic Optical and Magnetic Materials Condensed Matter::Materials Science Magnetization Paramagnetism 0103 physical sciences Magnetic force microscope 0210 nano-technology Néel temperature Magnetic dipole |
| Zdroj: | Journal of Magnetism and Magnetic Materials. 422:77-83 |
| ISSN: | 0304-8853 |
| Popis: | Nanocrystalline antiferromagnetic Mn35Ge35Te30 diluted magnetic semiconductors powder syntheses by the conventional direct reaction of pure metals. Nanocrystalline nature of the prepared sample confirmed using various techniques, where x-Ray diffraction (XRD) and atomic force microscope (AFM) measurements shows ~96 nm particle size, while transmission electron microscope (TEM) shows 92 nm particle size. XRD analysis show orthorhombic symmetry with lattice parameters a=7.386611±(0.0066) A, b=8.962502±(0.0090) A and c=7.027349±(0.0040) A. Electron Spin resonance (ESR) show a broad asymmetric line whereas the remnant Mn2+ six-hyperfine lines are broadened within |+1/2>→|−1/2> line according to high anisotropy; calculated Lande g-factor is 2.047. Vibrating sample magnetometer (VSM) analysis, field-moment characteristics revealed a hysteresis loop with small coercive field indicating that Mn35Ge35Te30 is a soft magnetic material. Moreover, hysteresis measurements at different temperatures show increasing magnetization with increasing temperature up to 150 K followed by decreased with increasing temperature up to 300 K. This behavior indicated to the antiferromagnetic nature of the prepared nanocrystalline materials. Magnetic moment – temperature measurements show Neel temperature TN=172.6 K. Magnetic force microscope revealed magnetic domains as a result of interaction between magnetic dipole moments of magnetic cantilever and pressed powder. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect