Fig. 1. Schematic of unit structure of cross-type terahertz filter

Fig. 2. Transmittance of cross-type terahertz filter. (a) Transmittance contour map of terahertz filter with H changing from 1 μm to 1000 μm; (b) transmittance curves of terahertz filters when H=10 μm and 150 μm

Fig. 3. Electric field distributions in slit of cross unit. (a) H=150 μm, f=0.57 THz; (b) H=150 μm, f=0.85 THz; (c) H=300 μm, f=0.85 THz; (d) H=750 μm, f=0.85 THz

Fig. 4. Linear fitting results. (a) Relationship between thickness and number of peaks at f=0.9 THz; (b) relationship between frequency and number of peaks at H=1000 μm

Fig. 5. Pictures of sample. (a) Sample on Al foil when thickness is 150 μm; (b) partially enlarged image; (c) optical microscopic image

Fig. 6. Terahertz time-domain waveforms and transmittance curves. (a) Time-domain waveforms of terahertz reference signal and filter sample signal; (b) terahertz transmittance curves obtained by FDTD simulation and experiment