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Eight-potential-well order-disorder ferroelectric model and effects of random fields

Zhi-Rong Liu·Bing-Lin Gu·Xiao-Wen Zhang
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Abstract

An eight-potential-well order-disorder ferroelectric model was presented and the phase transition was studied under the mean-field approximation. It was shown that the two-body interactions are able to account for the first-order and the second order phase transitions. With increasing the random fields in the system, a first-order phase transition is transformed into a second-order phase transition, and furthermore, a second-order phase transition is inhibited. However, proper random fields can promote the spontaneous appearance of a first-order phase transition by increasing the overcooled temperature. The connections of the model with relaxors were discussed.

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Zhi-Rong Liu, Bing-Lin Gu, Xiao-Wen Zhang. 2000-08-28. Eight-potential-well order-disorder ferroelectric model and effects of random fields. https://doi.org/10.1063/1.1327612

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