Zhang JianWei, Du XiaoPing, Wang XuPing, Zhao JiGuang, Liu Bing, Lv XiaoLei, Chen Pan, Song YiShuo, Wang Yang
Opt Lett. 2021 Sep 1;46(17):4192-4195. doi: 10.1364/OL.433525.
The electric-field-enhanced effect of permittivity can improve the performance of electro-optic modulators and deflectors. A theoretical model of super electro-optic modulation based on the field-enhanced effect of the permittivity was proposed. Results showed that a strong field-enhanced effect can greatly reduce the half-wave voltage and increase the modulation depth as a result of increased relative dielectric permittivity and permittivity gradient to the electric field. For bulk paraelectric KTN:Cu near the Curie temperature, we found a novel phenomenon that the response of relative dielectric permittivity to the bias electric field was closely related to the frequency, including attenuation, invariance, and enhancement. We effectively selected the frequencies corresponding to the strong field-enhanced effect by measuring the dielectric-frequency spectrum under the bias voltage. At these frequencies, a phase retardation of was achieved through 2 AC modulation voltage, indicating that the half-wave voltage was reduced by one order of magnitude.
介电常数的电场增强效应可以改善电光调制器和偏转器的性能。基于介电常数的电场增强效应，提出了一种超电光调制的理论模型。结果表明，由于相对介电常数和介电常数梯度随电场增加，强电场增强效应可大大降低半波电压并提高调制深度。对于居里温度附近的块状顺电体KTN:Cu，我们发现了一种新现象，即相对介电常数对偏置电场的响应与频率密切相关，包括衰减、不变和增强。通过测量偏置电压下的介电频谱，我们有效地选择了对应强电场增强效应的频率。在这些频率下，通过2个交流调制电压实现了π的相位延迟，表明半波电压降低了一个数量级。
