Magneto-dielectric coupling and non-ergodic electrical behaviour in hexagonal Sr0.6Ba0.4MnO3 via local strain driven magnetic ordering
| Autor: | Rawat, Ritu, Choudhary, R. J., Awasthi, A. M., Raghunathan, Rajamani, Sagdeo, Archna, Sinha, A. K., Chaudhary, S., Patnaik, S., Phase, D. M. |
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| Rok vydání: | 2019 |
| Předmět: | |
| Zdroj: | Journal of Magnetism and Magnetic Materials 497, 165972 (2020) |
| Druh dokumentu: | Working Paper |
| DOI: | 10.1016/j.jmmm.2019.165972 |
| Popis: | The crystal structure of hexagonal-Sr0.6Ba0.4MnO3 allows various competing superexchange interactions, leading to intriguing magnetic properties. Local structural changes modify overlapping between Mn and oxygen ions with temperature. Calculations based on our model spin-Hamiltonian reveal that the dominant linear antiferromagnetic superexchange interaction between the oxygen-linked Mn4+ ions results in short range correlations (SRC), manifesting a smooth drop in magnetization below 325K. Dominance of superexchange interaction changes its allegiance towards the non-linear oxygen-linked Mn-O-Mn interactions, onsetting long-range correlations (LRC) below 225K. Below the SRC-LRC crossover temperature, electrical response arising from the interacting dipoles exhibits power-law divergent behaviour of relaxation time, upon cooling. Non-ergodic character of the dipole-cluster glass state is examined via the indispensable aging and rejuvenation effects, similar to the spin glasses. Competitive-frustration among spin-exchange and local-strain is reckoned as responsible for the electrical glass origin. Comment: 20 pages, 6 figures, 32 references. arXiv admin note: substantial text overlap with arXiv:1807.01303 |
| Databáze: | arXiv |
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