ABSTRACT Ba(Zr0.2Ti0.8)O3-x(Ba0.7Ca0.3)TiO3 (BZT-xBCT) is a promising lead-free ferroelectric system with high piezoelectricity. Here we carry out phenomenological calculations to explore phase stability and electric field induced phase transition. Study of free energy variation near phase boundaries revealed ultralow energy barrier in single orthorhombic phase region and phase coexistence around inter-ferroelectric transitions. The calculated critical electric field for tetragonal-orthorhombic transition is in reasonable agreement with experimental data. Temperature–composition phase diagram under [001], [011] and [111] oriented electric field are computed, and polarization rotation associated monoclinic structures are studied.

中文翻译：

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无铅 Ba(Zr0.2Ti0.8)O3-(Ba0.7Ca0.3)TiO3 中的相界和电场诱导极化旋转

摘要 Ba(Zr0.2Ti0.8)O3-x(Ba0.7Ca0.3)TiO3 (BZT-xBCT) 是一种具有高压电性的无铅铁电系统。在这里，我们进行现象学计算以探索相稳定性和电场诱导相变。对相边界附近的自由能变化的研究揭示了单正交相区中的超低能垒和干涉铁电转变周围的相共存。计算出的四方-正交相变临界电场与实验数据合理吻合。计算了[001]、[011]和[111]取向电场下的温度-组成相图，并研究了极化旋转相关的单斜结构。