Terahertz near-field imaging with tapered sommerfeld-wire waveguides

In this work, we investigate the near-field properties of a tapered single wire waveguide, also known as a Sommerfeld-wire, for application in sub-wavelength terahertz near-field imaging. In reflection geometry, several waveguide terminations are investigated. Furthermore, to examine the imaging capability of a 20 mum radius taper tip, several metal structures were measured. Using a tapered Sommerfeld-wire, it was possible to resolve features corresponding to lambda/50 at 0.3 THz.