The optical phonon frequency and damping factor of Cadmium telluride (CdTe) have been investigated by using both the first-principles calculation and terahertz time-domain spectroscopy (TDS) system. The temperature dependence of transverse and longitudinal optical phonon frequency obtained by using the quasi-harmonic approximation is consistent with experimental results at the lower temperature range. Finally, the damping factors estimated from the three phonon contributions deviate from the extracted experimental data in the higher temperature range, which indicates the scattering process of four phonon plays an important role in anharmonic phenomena.

中文翻译：

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第一性原理和太赫兹时域光谱研究CdTe的介电和振动特性

通过第一性原理计算和太赫兹时域光谱（TDS）系统研究了碲化镉（CdTe）的光学声子频率和阻尼因子。通过准谐波近似获得的横向和纵向光学声子频率的温度依赖性与在较低温度范围内的实验结果一致。最后，在较高温度范围内，从三个声子贡献估计的阻尼因子与提取的实验数据有所不同，这表明四个声子的散射过程在非谐现象中起重要作用。