| Terahertz(THz) is electromagnetic wave in a wavelength between 0.03 mm and 3mm, and the frequency between 0.1T and 10 THz electromagnetic waves. The frequencies range between microwave and infrared light. With the rapid development of THz wave source technology and detection technology, THz communication technology has also been a great development, performance THz functional devices must also match. My paper designs three THz functional devices and test its performance.The main contents are as follows:1.We present a filter with polyimide(PI) as a substrate of flexible material. We used CST MWS simulation software simulate the filter, and the center frequencies were 0.53 THz, 1.23 THz,and the transmittance were 0.88,0.97, and bandwidth were 30%, 50%. Compared with the silicon substrate, the bandwidth and the transmittance increased greatly, but it made the center frequencies right. With the increasing of PI’s thickness, the three center frequencies moved to the left. The paper explored the preparation process of the device, and the final size of the filter was within reasonable limits. Using THz-TDS system transmission structure to do the test, we saw that the filter by silicon substrate had two filter pass-bands,and the center frequencies were 320 GHz and 1100 GHz, the transmittances were 0.5 and 0.6, the bandwidths were 30% and 50%. The filter made on PI had two pass-bands, and the center frequencies were 450 GHz and 1175 GHz, the transmittances were 0.4 and 0.95. Compared with the silicon substrate structure, they moved right of 130 GHz and 20 GHz, and transmittances were better than that on Si. The results were basically consistent.2.We proposed a filter based on split ring resonator structure(SRR). We used CST MWS simulation software for the device, and designed the construction. We prepared the filter, and tested them. We found that the filter had a transmittance peak at the frequency of 0.33 GHz, and the transmittance was 0.9, the bandwidth of 3dB was 72%; another transmittance peak at the frequency of 1.12 GHz, and the transmittance was 0.86, the bandwidth of 3dB was 48%.3.We explored the nature of strontium ferrite polarization deflection: we prepared strontium ferrite in five different sintering temperatures. We used THz-TDS system test samples and found the transmittance increasing with the decreases of sintering temperature. In addition, we built THz communication systems and tested samples transmittance and polarization in the deflection angle by the system. The polarization angle had changed slowly with the increasing of the sintering temperature. |
