Terahertz Modulators Based on Silicon Nanotip Array

摘要

As an attractive applications of terahertz (THz) radiation, imaging with THzrntechnique stands at the focus of current interest. THz spatial modulators arernkey issue for fast imaging with a single detector. Here, for the first time, thernsilicon nanotip (SiNT) arrays are reported that can be utilized as antireflectionrnlayers for the THz wave to achieve a low-loss and spectrally broadbandrnoptical-driven THz modulator. Compared with the modulator fabricated withrnbare silicon, a 2–3-time larger modulation depth is achieved in SiNT modulator.rnMoreover, it is found that the intrinsic THz transmission of SiNT is asrnhigh as 90%, which is much higher than that of bare silicon. The theoreticalrnsimulation results reveal that a strong antireflection effect induced from SiNTrnlayer plays a crucial role in enhancing the properties of modulator. The SiNTbasedrnoptical-driven THz modulator with low loss and high modulation depthrnis promising for potential application to THz imaging.