Electro-optic sampling of pulsed terahertz radiation by femtosecond laser pulses in noncollinear geometry in a 40 μ m thick layer of LiNbO 3 attached to a Si prism is experimentally demonstrated. Terahertz radiation is prism-coupled into the layer through its surface and modulates the frequency and angular spectra of the optical radiation propagating along the layer as a fundamental mode of a dielectric slab waveguide. The modulation results in the optical intensity variations in the optical beam transmitted through the layer. By measuring the intensity variations, we achieved 38 and 216 times enhancement in the sensitivity of electro-optic detection as compared to the conventional collinear ellipsometric technique with 1 mm thick ZnTe and 0.2 mm thick GaP crystals, respectively.

中文翻译：

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棱镜耦合的薄LiNbO 3层中太赫兹波的高灵敏电光检测

实验证明了飞秒激光脉冲在非共线几何形状中的40微米厚LiNbO 3层中附着在Si棱镜上的飞秒脉冲激光的电光采样。太赫兹辐射通过其表面棱镜耦合到该层中，并调制沿着该层传播的光辐射的频率和角谱，这是介电平板波导的基本模式。调制导致透射通过该层的光束的光强度变化。通过测量强度变化，与分别使用1 mm厚的ZnTe和0.2 mm厚的GaP晶体的常规共线椭偏技术相比，我们的电光检测灵敏度提高了38倍和216倍。