Investigations on the effect of magnetic ordering on dielectric relaxation in polycrystalline GdMn1-Fe O3
Autor: | Pattukkannu Murugavel, Arnab Pal |
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Rok vydání: | 2019 |
Předmět: |
010302 applied physics
Materials science Condensed matter physics Relaxation (NMR) 02 engineering and technology Dielectric Activation energy 021001 nanoscience & nanotechnology Condensed Matter Physics 01 natural sciences Electronic Optical and Magnetic Materials 0103 physical sciences Grain boundary Multiferroics Orthorhombic crystal system Dielectric loss Crystallite Electrical and Electronic Engineering 0210 nano-technology |
Zdroj: | Physica B: Condensed Matter. 555:99-105 |
ISSN: | 0921-4526 |
DOI: | 10.1016/j.physb.2018.11.057 |
Popis: | The influence of structural change and magnetic ordering on the dielectric relaxation has been studied for orthorhombic multiferroic GdMn1-xFexO3 (0 ≤ x ≤ 0.7) system. The frequency dependent dielectric constant and dielectric loss exhibit dispersion, suggesting a thermally activated relaxation process. The extracted activation energies attribute the relaxation process to charge hopping among the localized Mn/Fe sites. Interestingly, the composition dependent activation energy and characteristics frequency show a transition near x = 0.4 which is consistent with the observed subtle structural change and introduction of spin reorientation at this composition. The static orbital ordering associated with Jahn-Teller distortion and the evolution of magnetic ordering play a vital role in varying these parameters with composition. In addition, the activation energies obtained from impedance analysis support this fact and further reveal that both grain and grain boundary have significant contributions to the relaxation process. The study demonstrates the correlation between structural, dielectric and magnetic properties of the sample which can be tuned by compositional variation. |
Databáze: | OpenAIRE |
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