Intense and ultra-broadband Terahertz generation from metal foil

It has been observed that Terahertz (THz) wave was radiated from nanostructured metal gratings and metal films, which was illuminated by femtosecond laser pulse. In this paper, we got more than 60μ J intense single THz pulse, and the maximum spectrum was distributed from 0.3 to 149 THz. Theoretical calculation was performed to explain the generation mechanism.