Spectral dependences of components of the refractive index and absorption coefficient in a Li₂B₄O₇ (LB4) nonlinear crystal are determined in the THz range for the first time. Measurements have been carried out in the 0.15–1.6 THz (180–2000 μm) spectral range. The measured refractive index components are approximated by the Sellmeier dispersion equations subsequently used to determine the possible interaction types and to calculate the phase-matching angles for THz wave generation at the difference frequency between a Nd:YAG laser and a tunable laser source with a close wavelength. The efficiency of the process is estimated.

中文翻译：

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LI 2 B 4 O 7晶体的光学性质和太赫兹辐射的产生

首次在THz范围内确定Li ₂ B ₄ O ₇（LB4）非线性晶体中折射率和吸收系数的成分与光谱的关系。在0.15–1.6 THz（180–2000μm）光谱范围内进行了测量。测得的折射率分量由Sellmeier色散方程式近似，随后用于确定可能的相互作用类型并计算在Nd：YAG激光器和可调激光源之间的差频下太赫兹波产生的相位匹配角波长。估计过程的效率。