Abstract The flexoelectricity describes the contribution of the linear couplings between the electric polarization and strain gradient and between polarization gradient and strain to the thermodynamics of a solid and represents the amount of polarization change of a solid arising from a strain gradient. Although the magnitude of the flexoelectric effect is generally small, its contribution to the overall thermodynamics of a solid may become significant or even dominant at the nanometer scale. Recent experimental and computational efforts have led to significant advances in our understanding of the flexoelectric effect and its exploration of potential applications in devices such as sensors, actuators, energy harvesters, and nanoelectronics. Here we review the theoretical development and experimental progress in flexoelectricity including the types of materials systems that have been explored and their potential applications. We discuss the challenges in the experimental measurements and density functional theory computations of the flexoelectric coefficients including understanding the order of magnitude discrepancies between existing experimentally measured and computed values. Finally, we offer a perspective on the future directions for research on flexoelectricity.

中文翻译：

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固体中的柔性电：进展、挑战和前景

摘要 挠曲电性描述了电极化与应变梯度之间以及极化梯度与应变之间的线性耦合对固体热力学的贡献，并表示由应变梯度引起的固体的极化变化量。尽管挠曲电效应的幅度通常很小，但它对固体整体热力学的贡献在纳米尺度上可能变得显着甚至占主导地位。最近的实验和计算工作使我们对挠曲电效应的理解及其在传感器、执行器、能量收集器和纳米电子设备等设备中潜在应用的探索取得了重大进展。在这里，我们回顾了柔性电的理论发展和实验进展，包括已探索的材料系统类型及其潜在应用。我们讨论了挠电系数的实验测量和密度泛函理论计算中的挑战，包括了解现有实验测量值和计算值之间的数量级差异。最后，我们对柔性电研究的未来方向提出了展望。我们讨论了挠电系数的实验测量和密度泛函理论计算中的挑战，包括了解现有实验测量值和计算值之间的数量级差异。最后，我们对柔性电研究的未来方向提出了展望。我们讨论了挠电系数的实验测量和密度泛函理论计算中的挑战，包括了解现有实验测量值和计算值之间的数量级差异。最后，我们对柔性电研究的未来方向提出了展望。