Optical Fiber Laser-THz Emission Microscope

We report the fabrication of an optical-fiber terahertz emitter with a 45-degree wedged tip coated with InAs thin film. The mechanism of terahertz generation from the optical fiber tip is explained by the photo-Dember effect in low-band gap semiconductor. Applications of the devised terahertz emitter can be extended to near-field sub-wavelength imaging, spectroscopy, polarization studies and remote sensing.