Terahertz Modulators Based on Silicon Nanotip Array. Issue 2 (4th December 2017)

• Record Type: Journal Article
• Authors: Shi, Zhong‐Wei; Cao, Xing‐Xing; Wen, Qi‐Ye; Wen, Tian‐Long; Yang, Qing‐Hui; Chen, Zhi; Shi, Wen‐Sheng; Zhang, Huai‐Wu
• Is Part Of: Advanced optical materials. Volume 6:Issue 2(2018)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2017-12-04
• Subjects: antireflection effect -- enhanced modulation depth -- modulators -- silicon nanotips -- terahertz waves; Optical materials -- Periodicals; Photonics -- Periodicals; 620.11295
• DOI: 10.1002/adom.201700620
• Languages: English
• ISSNs: 2195-1071

Abstract

Abstract: As an attractive applications of terahertz (THz) radiation, imaging with THz technique stands at the focus of current interest. THz spatial modulators are key issue for fast imaging with a single detector. Here, for the first time, the silicon nanotip (SiNT) arrays are reported that can be utilized as antireflection layers for the THz wave to achieve a low‐loss and spectrally broadband optical‐driven THz modulator. Compared with the modulator fabricated with bare silicon, a 2–3‐time larger modulation depth is achieved in SiNT modulator. Moreover, it is found that the intrinsic THz transmission of SiNT is as high as 90%, which is much higher than that of bare silicon. The theoretical simulation results reveal that a strong antireflection effect induced from SiNT layer plays a crucial role in enhancing the properties of modulator. The SiNT‐based optical‐driven THz modulator with low loss and high modulation depth is promising for potential application to THz imaging. Abstract : New applications in the realms of terahertz (THz) technology require versatile adaptive optics and powerful modulation techniques. Semiconductors have proven to provide fast and broadband all‐optical THz wave modulation. In this work, the silicon nanotip arrays on silicon substrate are utilized as antireflection layers for the THz wave, achieving a low‐loss and spectrally broadband optical‐driven THz modulator with remarkably enhanced modulation depth.