Terahertz Modulators Based on Silicon Nanotip Array

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.

[1]  Wai Lam Chan,et al.  Imaging with terahertz radiation , 2007 .

[2]  M. Koch,et al.  Terahertz spectroscopy and imaging – Modern techniques and applications , 2011 .

[3]  Chun-Hsing Li,et al.  A 340-GHz Heterodyne Receiver Front End in 40-nm CMOS for THz Biomedical Imaging Applications , 2016, IEEE Transactions on Terahertz Science and Technology.

[4]  E. Holzhauer,et al.  High-speed switching of far-infrared radiation by photoionization in a semiconductor. , 1992, Applied optics.

[5]  Gang Chen,et al.  Analysis of optical absorption in silicon nanowire arrays for photovoltaic applications. , 2007, Nano letters.

[6]  David Shrekenhamer,et al.  High speed terahertz modulation from metamaterials with embedded high electron mobility transistors. , 2011, Optics express.

[7]  Koichiro Tanaka,et al.  Photo-designed terahertz devices , 2011, Scientific reports.

[8]  Min-Yi Shih,et al.  Strong broadband optical absorption in silicon nanowire films , 2007 .

[9]  Yan Zhang,et al.  Spatial Terahertz Modulator , 2013, Scientific Reports.

[10]  D. Jena,et al.  Broadband graphene terahertz modulators enabled by intraband transitions , 2012, Nature Communications.

[11]  M. Rahm,et al.  Spectrally wide-band terahertz wave modulator based on optically tuned graphene. , 2012, ACS nano.

[12]  M. Koch,et al.  Room-temperature operation of an electrically driven terahertz modulator , 2004 .

[13]  Ranjan Singh,et al.  Tuning the resonance in high-temperature superconducting terahertz metamaterials. , 2010, Physical review letters.

[14]  Lin Kang,et al.  Low loss and magnetic field-tunable superconducting terahertz metamaterial. , 2010, Optics express.

[15]  Zhiyong Zhong,et al.  Enhanced Optical Modulation Depth of Terahertz Waves by Self‐Assembled Monolayer of Plasmonic Gold Nanoparticles , 2016 .

[16]  David Shrekenhamer,et al.  Terahertz single pixel imaging with an optically controlled dynamic spatial light modulator. , 2013, Optics express.

[17]  M. Povinelli,et al.  Optical absorption enhancement in silicon nanowire arrays with a large lattice constant for photovoltaic applications. , 2009, Optics express.

[18]  Zongfu Yu,et al.  Optical absorption enhancement in amorphous silicon nanowire and nanocone arrays. , 2009, Nano letters.

[19]  G. Dodel,et al.  Amplitude-, phase-, and frequency modulation of far-infrared radiation by optical excitation of silicon , 1991 .

[20]  Willie J Padilla,et al.  Ultrafast optical switching of terahertz metamaterials fabricated on ErAs/GaAs nanoisland superlattices. , 2007, Optics letters.

[21]  Debdeep Jena,et al.  Unique prospects for graphene-based terahertz modulators , 2011 .

[22]  Yingli Liu,et al.  Terahertz metamaterials with VO2 cut-wires for thermal tunability , 2010 .

[23]  Yuanjie Su,et al.  Mechanism of optical absorption enhancement of surface textured black silicon , 2013, Journal of Materials Science: Materials in Electronics.

[24]  P. Siegel Terahertz technology in biology and medicine , 2004, IEEE Transactions on Microwave Theory and Techniques.

[25]  Tuning the phase transitions of VO2 thin films on silicon substrates using ultrathin Al2O3 as buffer layers , 2014 .

[26]  Wensheng Shi,et al.  Using Si and Ge nanostructures as substrates for surface-enhanced Raman scattering based on photoinduced charge transfer mechanism. , 2011, Journal of the American Chemical Society.

[27]  Robert A. Street,et al.  Reflectivity of disordered silicon nanowires , 2008 .

[28]  Tadao Nagatsuma,et al.  A Review on Terahertz Communications Research , 2011 .

[29]  Wai Lam Chan,et al.  A spatial light modulator for terahertz beams , 2009 .

[30]  Yong-Zhong Xiong,et al.  A fundamental OOK modulator for 340 GHz communication using 0.13 μm CMOS technology , 2015 .

[31]  Saroj Rout,et al.  A low-voltage high-speed terahertz spatial light modulator using active metamaterial , 2016 .

[32]  Shui-Tong Lee,et al.  High-performance surface-enhanced Raman scattering sensors based on Ag nanoparticles-coated Si nanowire arrays for quantitative detection of pesticides , 2010 .

[33]  Michael Pepper,et al.  Terahertz spectroscopy: Signatures and fingerprints , 2008 .

[34]  Qi-Ye Wen,et al.  Graphene based All-Optical Spatial Terahertz Modulator , 2014, Scientific Reports.

[35]  Lei Liu,et al.  Photo-induced spatial modulation of THz waves: opportunities and limitations. , 2015, Optics express.

[36]  W. H. Lowdermilk,et al.  Graded‐index antireflection surfaces for high‐power laser applications , 1980 .

[37]  Yia-Chung Chang,et al.  Manipulative depolarization and reflectance spectra of morphologically controlled nano-pillars and nano-rods. , 2009, Optics express.

[38]  Qi-Ye Wen,et al.  High-speed and broadband terahertz wave modulators based on large-area graphene field-effect transistors. , 2014, Optics letters.

[39]  David R. Smith,et al.  Terahertz compressive imaging with metamaterial spatial light modulators , 2014, Nature Photonics.

[40]  S. T. Lee,et al.  Fabrication of Single‐Crystalline Silicon Nanowires by Scratching a Silicon Surface with Catalytic Metal Particles , 2006 .

[41]  Lei Liu,et al.  Optical Modulation of Continuous Terahertz Waves towards Cost-effective Reconfigurable Quasi-optical Terahertz Components References and Links , 2022 .