Waveguide having a cladded core for guiding terahertz waves

A waveguide for guiding a terahertz wave with a wavelength ranging from 0.1 to 3 mm comprising:

• a single layer cladding tube made of a metal-free dielectric material, and having an inner peripheral surface, an outer peripheral surface surrounding said inner peripheral surface, and a thickness defined between said inner and outer peripheral surfaces, said inner peripheral surface confining a transmission space;
• and
• a core filling said transmission space, said core having a refractive index lower than that of said cladding tube and a minimum width larger than the wavelength of the guided terahertz wave, said thickness of said cladding tube being smaller than one half of said width of said core;
• wherein said core has an attenuation constant for the guided terahertz wave lower than that of said cladding tube.