太赫兹技术的重要应用急需准确的太赫兹辐射功率计量作为支撑和保障，国际计量局组织开展了国际首次太赫兹辐射功率测量比对。为实现太赫兹辐射功率准确测量，保障我国太赫兹功率计量取得国际等效互认，报导了全吸收型太赫兹辐射功率计，对太赫兹辐射功率计的计量性能和测量不确定度进行详细分析和实验测试。利用一种具有镜反射的太赫兹辐射计，对全吸收型太赫兹辐射计的计量性能进行实验验证，保障了太赫兹辐射功率计响应度量值的准确性和不确定度分析的合理性。利用自主研制的太赫兹辐射计参加国际首次太赫兹功率比对，取得了国际等效一致。

针对太赫兹(1 THz=1012 Hz)电容器件发展的需求，研究了呈现巨介电和不呈现巨介电两种状态CaCu3Ti4O12(CCTO)陶瓷在THz波段的介电响应特性。在微波波段，小颗粒(Φ<2 μm)CCTO 的介电常数εr＜700，无巨介电特征，而大颗粒(Φ>10 μm)CCTO 的εr＞2000，呈现巨介电特征；两组CCTO 陶瓷的介电损耗值Tan δ在0.1~0.6之间。然而，在THz波段，两种颗粒度CCTO 的介电常数几乎完全相等(εr=72±3)，且损耗不超过0.18。实验结果表明，CCTO 陶瓷组分的离子极化率主导了在THz波段的介电常数εr，而大颗粒CCTO 对THz电磁波的散射超过小颗粒CCTO，导致介电损耗值Tan δ上升。因此，在THz波段，降低CCTO 颗粒大小不会影响介电常数，反而能够降低介电损耗。这一结果表明CCTO 陶瓷是制备THz波段电容的理想介电材料。

Conventional analytical methods in the wavelet domain are used to present an analysis of terahertz (THz) waveguide modes. To obtain THz radiation pulses passing through a waveguide, we build a simple experimental system with a 5-mm-long, 230-\mum-inner-diameter stainless steel waveguide. The single-mode guided signal from the experiments and the multi-mode signal of a similar THz waveguide reported in the literature are analyzed using the continuous wavelet transform (CWT). The results demonstrate that analyzing THz waveguide modes in the wavelet domain not only possesses all the functionality of the traditional THz time-domain spectroscopy (TDS) data processing but also has the ability to unscramble quantitatively and intuitively detailed information about the target samples, such as mode type, cut-off frequency, amplitude distinction, and group velocity.