Integrated optical waveguide sensor has characteristics of good insulation, broadband response and small size. A LiNbO3 (LN) integrated optical waveguide sensor based on a dual parallel asymmetric Mach-Zehnder interferometer (DAMZI) and segmented electrode is designed, fabricated and experimentally demonstrated. By using the DAMZI with segmented electrode fabricated between the two straight waveguide arms, a push-pull modulation is generated, yielding a pair of differential signals are formed at the two outputs of the sensor. Thus based on the differential effect of the balanced photo detection (PD) at the receiving end, the noise is suppressed while the signal is enhanced. The noise floor, minimum detectable electric field, and input/output characteristics of the sensor are measured and compared with those of the sensor with single PD. Experiment results demonstrate that in comparison to the sensor with single PD, the noise floor of the sensor with balanced PD is reduced by about 6 dB while the minimum detectable electric field is reduced by about 18 dB. Besides, in the time domain, the minimum detectable electric field and dynamic range of the sensor are 12.5 V/m and 47 dB respectively. The frequency response variation is within ±1 dB from 9 kHz to 340 MHz, and the temperature stability variation is less than ±0.3 dB with the ambient temperature changed from 18 °C to 28 °C within 19 hours. All these results demonstrate that the sensor has powerful potential capability to be used for measuring the weaker electric field in the electromagnetic compatibility (EMC) area.

中文翻译：

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基于双并行马赫曾德干涉仪的光波导电场传感器


集成光波导传感器具有绝缘性好、响应宽带、体积小等特点。基于双并行非对称马赫曾德尔干涉仪（DAMZI）和分段电极的LiNbO3（LN）集成光波导传感器的设计、制造和实验演示。通过使用在两个直波导臂之间制作分段电极的 DAMZI，生成推挽调制，从而在传感器的两个输出处形成一对差分信号。因此，基于接收端平衡光电检测（PD）的微分效应，在增强信号的同时抑制了噪声。测量传感器的本底噪声、最小可检测电场和输入/输出特性，并与单 PD 传感器进行比较。实验结果表明，与单PD传感器相比，平衡PD传感器的本底噪声降低了约6 dB，最小可检测电场降低了约18 dB。此外，在时域上，传感器的最小可检测电场和动态范围分别为12.5 V/m和47 dB。从9kHz到340MHz频率响应变化在±1dB以内，19小时内环境温度从18℃变化到28℃时温度稳定性变化小于±0.3dB。所有这些结果表明，该传感器具有强大的潜在能力，可用于测量电磁兼容（EMC）领域的较弱电场。