| Autor: |
Santhoshkumar Mahadevan, Puneet Sharma |
| Rok vydání: |
2020 |
| Předmět: |
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| Zdroj: |
Journal of Magnetism and Magnetic Materials. 514:167174 |
| ISSN: |
0304-8853 |
| Popis: |
The conduction and charge transport mechanism of cobalt substituted barium hexaferrite (BaCoM) were studied by impendence spectroscopy at different temperatures and compared with BaM. Frequency dependent impedance spectra showed two distinct relaxations in BaM whereas a single relaxation peak was present in BaCoM. The relaxation frequencies were found to be temperature dependent. Scaling behaviour confirmed the dynamic conduction process is temperature independent and deviates from Debye type relaxation. Brick layer model has been employed to investigate the charge conduction through grain and grain boundaries. Arrhenius plot of conductivity showed two sharp transitions in three different temperature regime which indicates parallel conduction mechanism in the system. The frequency dependent conductivity was fitted with Jonscher’s power law at different temperatures. The variation in frequency exponent with temperature confirmed the evidence of three types of conduction process. Higher conductivity and different transition temperature was observed for BaCoM as compared to BaM. The conduction process was in accordance with overlapping-large polaron tunnelling model. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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