Study of ultrabroadband terahertz radiation from wedge-shaped ZnTe

We report detailed thickness dependence of ultrabroadband terahertz (THz) radiation using wedge-shaped ZnTe. The spectral width and intensity of the radiation strongly depend on the thickness. The THz radiation at /spl sim/10-/spl mu/m thickness has a pulse width of /spl sim/50 fs and the spectrum extends up to /spl sim/50 THz. Several spectral dips whose frequency depends on the thickness systematically are observed and explained by the phase matching condition.