M. K. Mridha, A. Mazhorova, M. Clerici,  I. Al-Naib, M. Daneau, X. Ropagnol, M. Peccianti, C. Reimer, M. Ferrera, L. Razzari, F. Vidal and Roberto Morandotti, “Active terahertz two-wire waveguides”, Opt. Express 22, 22340 (2014).

 (a) Schematic for the dielectric support holder for the wires of diameter 250 μm. The central hole is 800 μm in diameter, while the separation between the two wires is 300 μm. (b) Top-view of the experimental setup used for calibrating the maximum signal attainable from the GaAs integrated semi-large area PC antenna. The emitted THz radiation is focused onto a ZnTe crystal. Changes in the probe beam (800 nm) polarization are measured using a Wollaston prism and photo detectors (PDs). (c) Details of the integrated semi-large area PC antenna used to generate THz radiation, (d) schematic of the passive configuration where the THz radiation from the integrated semi-large area PC antenna is coupled into the two-wire waveguide, (e) schematic of the active configuration; here both the generation and the coupling of the THz radiation occur directly inside the two-wire waveguide. The arrows indicate the direction of the THz radiation emitted in each case in the plane containing the two wires.

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