Terahertz(THz) radiation, lies in the frequency gap between the infrared and microwaves,typicaly referred to as the frequencies from 100GHz to 30THz. Recent technological innocation in photonics and nanotechnology is now enabling THz research to be applied in many more sectors.It is finding use in information and communications technology;ultrafast computing; non-destructive evaluation;homeland security;quality control; biology and medical sciences et al. Our group dedicates on building table top high power THz source and use it in THz spectroscopy study of novel materials.