Terahertz beam generation by femtosecond optical pulses in electro-optic materials

We have observed subpicosecond pulses having terahertz bandwidths generated from electro-optic materials by using femtosecond optical pulses. The time-resolved radiation signal clearly indicates that the terahertz radiation comes from the regions within the coherence length near the surfaces of electro-optic materials under the phase-mismatched condition. When the high-energy femtosecond laser pulses are used, this method provides a new way to generate large amplitude broad bandwidth terahertz radiation efficiently.