Developing large electro-optic (EO) effect material is crucial technology for developing current levels of optical communication, and the lanthanum-modified lead zirconate titanate (PLZT) transparent thin films with an excellent theoretical quadratic EO coefficient has been paid great attention. High-quality PLZT thin films have been fabricated by improved sol–gel, including multiple spin coating and plasma annealing. The XRD patterns show the PLZT thin films with preferred (110) orientations and highly crystallized on the ITO/SiO₂ substrate. The PLZT thin films are smooth and crack-free and can achieve a maximum transmittance of 93.8%. The piezo-response force microscopy images of the thin film reveal that non-180° domain determines the magnitude of the EO coefficient and plays vital role in the piezoelectric response. Furthermore, the effective quadratic EO coefficients of PLZT thin films are obtained by the designed test system. The quadratic EO measurements indicate excellent quadratic Kerr coefficient of 3.54 × 10^–15 m²/V², and the optical modulation effect of the EO modulator based on PLZT thin films is almost consistent with the theory and has low insertion losses. The PLZT thin films made in this study are a competitive candidate material as an optical modulator for modern optical communication.

中文翻译：

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用于光通信集成设备的PLZT薄膜的大二次电光效应

开发大型电光（EO）效应材料是发展当前光通信水平的关键技术，具有优异的二次方EO系数的镧改性钛酸锆钛酸铅（PLZT）透明薄膜受到了广泛关注。通过改进的溶胶-凝胶，包括多次旋涂和等离子退火，可以制造出高质量的PLZT薄膜。XRD图谱显示具有优选（110）取向并在ITO / SiO ₂上高度结晶的PLZT薄膜基质。PLZT薄膜光滑无裂纹，可实现93.8％的最大透射率。薄膜的压电响应力显微镜图像显示，非180°域决定了EO系数的大小，并且在压电响应中起着至关重要的作用。此外，通过设计的测试系统获得了PLZT薄膜的有效二次EO系数。二次EO测量结果表明，出色的二次Kerr系数为3.54×10 ^–15 m ² / V ²，基于PLZT薄膜的EO调制器的光调制效果几乎与理论相符，插入损耗低。这项研究中制作的PLZT薄膜是竞争性候选材料，可作为现代光通信的光调制器。