  Irradiation of a thin metallic wire with an intense femtosecond laser pulse
creates a strong discharge wave that travels as a narrow pulse along the wire
surface. The travelling discharge efficiently emits secondary radiation with
spectral characteristics mostly defined by the wire geometry. Several exemplary
designs are considered in the context of generation of intense terahertz
radiation with controllable characteristics for various scientific and
technological applications. The proposed setup benefits by its robustness,
versatility and high conversion efficiency of laser energy to terahertz
radiation, which reaches several percent.
