太赫兹光谱技术检测水分及水合作用的研究进展 Research in Moisture and Hydration Detection by Terahertz Time Domain Spectroscopy

太赫兹(Terahertz, THz)辐射，通常指的是频率在0.1 THz~10 THz (波长在3 mm~30 μｍ)之间的电磁波，该波段在微波和红外之间，属于远红外和亚毫米波范畴。同X射线、可见光等电磁辐射一样，可作为物体成像的光源，其成像和光谱技术可以提供微波和X射线技术所不能提供的信息。太赫兹波脉冲宽度在亚皮秒量级，光子能量和高时空相干性，包含分子转动和振动信息。本文总结了太赫兹成像技术在水分检测和水分成像中的应用，综述了太赫兹成像在医疗、林业、农业和食品中的应用、取得的成果和亟待解决的问题。同时综述了太赫兹时域光谱技术在水合作用检测中的应用，提出本实验室的研究进展。 The terahertz (THz) radiation occupies a large portion of the electromagnetic spectrum between the microwave and infrared bands. It refers to the frequency between the 0.1 THz to 10 THz (the wavelength is 3 mm to 30 μm). Since it possesses many attractively characteristic properties, THz imaging and sensing technologies can provide information not available through conventional methods such as microwave and X-ray techniques. THz waves contain rich information involved in molecular vibration and rotation, and have sub-picoseconds pulse width, low photon energy, and high space-time coherence. Combined with the terahertz imaging systems of transmission type and reflection type, a general review of its application in medical applications, forestry products, agriculture/food products by using THz time domain scan-imaging technology is provided. The achievements and the problems to be solved are also discussed. We also reviewed the water structure and interaction in the solution detected by terahertz time spectroscopy and conducted the research of our study.