The electric-field-enhanced effect of permittivity is one of the most important physical properties of KTa_1-xNb_xO₃ in paraelectric, thus greatly affecting the performance of electro-optic modulator and deflector. We studied the temperature dependence of the electric-field-enhanced effect and the effect of supercooling on it. We found that this enhanced effect is closely related to the Fröhlich entropy, with a minimum value that corresponds to the strongest field enhancement effect. We further discovered that supercooling could improve the field-enhanced effect by 15%, because of the small polar nanoregion (PNR) size and high polarization. In addition, we propose a novel model to describe the electric-field-enhanced characteristic of the permittivity. The model can well explain the enhanced permittivity under DC electric field and reveal that the field enhancement of permittivity is mainly caused by reorientation of PNRs gradually activated by the DC electric field.

介电常数的电场增强作用是KTa _1-x Nb _x O ₃的最重要物理性质之一在顺电中，因此极大地影响了电光调制器和偏转器的性能。我们研究了电场增强效应和过冷效应对其的温度依赖性。我们发现，这种增强效应与Fröhlich熵密切相关，其最小值对应于最强的场增强效应。我们进一步发现，由于极性纳米区域（PNR）的尺寸较小且极化程度较高，因此过冷可以将场增强效果提高15％。此外，我们提出了一种新颖的模型来描述介电常数的电场增强特性。