We investigate the electrostrictive response across a ferroelectric phase transition from first-principles calculations and show that $M$, the field-induced electrostrictive tensor, controlling the amplitude of the electric-field induced strain, can be made arbitrarily large through strain engineering. We take as a case study the epitaxial strain-induced transition from para- to ferroelectricity of ${\mathrm{KTaO}}_3$. We show that the magnitude of the field-induced electrostriction diverges with the permittivity at the transition, hence exhibiting giant responses through a calculation of both the $M$ and $Q$ electrostrictive tensors. We explain the origin of this giant electrostrictive response in ${\mathrm{KTaO}}_3$ using a microscopic decomposition of the electrostriction coefficients, and use this understanding to propose design rules for the development of future giant electrostrictors for electromechanical applications. Finally, we introduce a further means to calculate electrostriction, specific to ferroelectrics, and not yet utilized in the literature.

中文翻译：

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KTaO3 中的应变工程发散电致伸缩

我们通过第一性原理计算研究了铁电相变中的电致伸缩响应，并表明$米$，场致电致伸缩张量，控制电场致应变的幅值，可以通过应变工程任意变大。我们以外延应变引起的从顺电到铁电的转变作为案例研究${\mathrm{KTaO}}_3$. 我们表明，场致电致伸缩的大小与跃迁时的介电常数不同，因此通过计算$米$和$问$电致伸缩张量。我们解释了这种巨大的电致伸缩反应的起源${\mathrm{KTaO}}_3$使用电致伸缩系数的微观分解，并利用这种理解为未来机电应用的巨型电致伸缩器的开发提出设计规则。最后，我们介绍了另一种计算电致伸缩的方法，该方法专门针对铁电体，尚未在文献中使用。