太赫兹科学与技术进展-张希成.pptVIP

Recent Progress for THz Science Technology NRC Report: Harnessing Light Wave’s Nature: Diffraction Wave’s Nature: Diffraction Young’s Experiment T-射线 的一些重要特性 T-射线 具有较低光子能量 (4 meV @ 1 THz) ，不会在生物组织中产生有害的光致电离。 很多有机分子由于偶极子的旋转和震动跃迁, 在 GHz 到 THz 频段，都具有很强的吸收和色散；分子的这些光谱特征使得T-射线 鉴别成为可能。 相干T-射线 信号瞬时电场的强度和相位可以同时被测量; 这样我们就可以通过对T-射线 进行时域探测，获得THz 吸收光谱和色散光谱。 THz 时域光谱提供了非常高的信噪比，而且对黑体辐射 (热背景)不敏感。 The Breadth of T-Ray Applications Research Highlights in Year 2002 Solid state THz laser (Italy and UK) High power THz source from Jefferson Lab (US) T-ray tomographic imaging (US) THz resonant structure for label-free DNA detection (Germany) T-ray for biological and chemical agents sensing and imaging (US) THz radiation from semiconductor under strong B field (Japan) Nonlinear THz wave spectroscopy (US) THz wave quantum optics and quantum computing (US) THz wave for medical application (Europe and US) T-Ray Imaging and Tomography Why T-ray imaging modality? Functional imaging! T-ray imaging with standard x-y scan Transmission and reflection mode Tomography T-ray computed tomography (CT) T-ray diffractive tomography (DT) Tomography with a binary lens and a broadband pulse T-Ray Image of A Letter Contains Powders T-射线用于对抗生物恐怖主义 Thurengiensis 杆状菌 孢子被放入信封中。 THz像中其吸收/ 散射清晰可见， 但是为了准确地辨别，需要对样品的THz 响应进行全面的分析。 T-射线 透视衣物？ 为了加强执法力度? T-射线收发器 飞行时间 T-射线成像 一块火鸡骨头的T-射线 CT 一个球状物体(f=36 mm)的T-射线 CT成像 2-, 4-, and 8-Level T-Ray Fresnel Lenses Tomography with a T-Ray Binary Lens Future Work for T-Ray Imaging Problems need to be solved: [1] Imaging Time should be from hours to less than one minute, with a target time of a few seconds. [2] Imaging Area should be from 2 cm to 20 cm, with a target area of 40 cm. [3] Imaging Resolution should be from 3 mm to sub-mm, with a target resolution of 0.1 mm. [4] Imaging Distance should be from 20 cm to 2 meter, with a target distance of a few hundred meters. Prof. Ci-Ling Pan’s THz Lab (Clean-Room) THz Lab at Capital Normal University of Beijing THz La