Terahertz frequency-selective surface and guided-mode resonance f lters

We report on the experimental and theoretical investigation of a new class of terahertz f lters based on frequencyselective surfaces patterned on thin foils of the low-loss cycloolef n polymer Zeonor. We observe both broad and narrowband resonances, which stem from the FSS response and the coupling to substrate guided modes, respectively. The f ltering properties are studied as a function of the FSS geometry and the thickness of the polymer layer. Very narrow linewidths with quality factors exceeding 100 are measured experimentally and theoretically conf rmed via f nite-element simulations.