In this paper, we present experimentally the transmission properties of THz pulse through subwavelength planar fractal
slits on the copper foil. The transmission measurement is carried out using THz time-domain spectroscopy. THz
spectroscopy of these fractal slits shows the featured frequency selectivity. Multiple band gaps and pass bands for THz
wave are observed. THz transmission under different polarization for a 7-level fractal pattern is analyzed. The
transmission spectra with the different levels of fractal slits are compared and discussed. Polarization dependent THz
transmission is attributed to the localized resonance induced by the fractal pattern.
We experimentally investigate the resonantly enhanced transmission of the terahertz radiation through a periodic array of
subwavelength apertures on metal films. We fabricated the periodic arrays of subwavelength apertures with different
periods and different diameters on silicon substrate. THz transmission spectra of these samples are measured by means
of terahertz time-domain spectroscopic system. The resonantly enhanced transmissions with the frequency selectivity are
observed. Our experimental results show that the resonantly transmission peak appears red shift and increases with
increasing of hole diameter when keeping the period of array as a constant. On the other hand, the resonantly
transmission peak with the same hole diameter appears red shift with increasing of the array period.