Studies on dielectric relaxation in ceramic multiferroic Gd1-xYxMnO3
Autor: | Sarguna, R. M., Sridahran, V., Awasthi, A. M., Subramanian, N. |
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Rok vydání: | 2017 |
Předmět: | |
Zdroj: | J. American Ceramic Society 100(6), 2596 (2017) |
Druh dokumentu: | Working Paper |
DOI: | 10.1111/jace.14758 |
Popis: | Dielectric study over a broadband was carried out from 10 to 70 K on ceramic Gd1-xYxMnO3 (x= 0.2, 0.3, and 0.4). For all the compositions, a prominent sharp peak about ~18K was observed in the temperature dependence of both {\epsilon}'(T) and {\epsilon}"(T) at all frequencies, indicating a long-range ferroelectric (FE) transition. Using Cole-Cole fit to the permittivity data, the relaxation time {\tau} and the dielectric strength {\Delta}{\epsilon} were estimated. Temperature variation of {\tau}(T) in the Arrhenius representation is found to be nonlinear (non-Debyean relaxation), with increasing barrier-activation energy over successive temperature-windows. Interestingly, for all the compositions, we witness a jump in {\tau}(T) about the ferroelectric transition temperature, concurred by a broad-maximum in {\Delta}{\epsilon}(T), signifying the critical slowdown of relaxations near long-range FE-correlations. Comment: 20 Pages, 10 Figures, 1 Table, and 14 References |
Databáze: | arXiv |
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