Anti-reflection implementations for terahertz waves


Undesired reflection caused by impedance mismatch can lead to significant power loss and other unwanted effects. In the terahertz regime, anti-reflection method has evolved from simple quarter-wave antireflection coating to sophisticated metamaterial device and photonic structures. In this paper, we examined and compared the theories and techniques of several antireflection implementations for terahertz waves, with emphasis on gradient index photonic structures. A comprehensive study is presented on the design, fabrication and evaluation of this new approach.

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Corresponding authors

Correspondence to Yuting W. Chen or Xi-Cheng Zhang.

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Yuting W. Chen received the B.S. degree in electrical engineering from the University of Illinois-Urbana Champaign in 2007, the M. S. and Ph.D. degrees in electrical engineering from Rensselaer Polytechnic Institute (RPI) in 2009 and 2011, respectively. During her graduate study, she was a National Science Foundation IGERT Fellow in the Center for Terahertz Research at RPI. Her research was in the area of silicon photonic structures for broadband anti-reflection of terahertz waves. She was the recipient of the Founders Award of Excellence at RPI in 2009 and holds two U.S. patents. Dr. Chen is currently with IBM at Poughkeepsie, NY.

Xi-Cheng Zhang-Parker Givens Chair of Optics, assumes Directorship of The Institute of Optics, University of Rochester (UR), NY, a foremost institution in optics and optical physics research and education, on 1/1/2012. Prior to joining UR, he pioneered worldleading research in the field of ultrafast laserbased terahertz technology and optical physics at Rensselaer Polytechnic Institute (RPI), Troy NY (1992–2012). At RPI, he is the Eric Jonsson Professor of Science; Acting Head at the Department of Physics, Applied Physics & Astronomy; Professor of Electrical, Computer & System; and Founding Director of the Center for THz Research. He is co-founder of Zomega Terahertz Corp. With a B.S. (1982) from Peking University, he earned the M.S. (1983) and Ph.D. degree (1985) in Physics from Brown University, RI.

Previous positions included Visiting Scientist at MIT (1985), Physical Tech. Division of Amoco Research Center (1987), EE Dept. at Columbia University (1987–1991); Distinguished Visiting Scientist at Jet Propulsion Lab, Caltech (2006). He holds 27 U.S. patents, and is a prolific author and speaker. He is a Fellow of AAAS, APS (lifetime), IEEE, and OSA (lifetime). Dr. Zhang served as Editor-in-Chief of Optics Letters (2014–2016).

His honors and awards include: IRMMW-THz Kenneth Button Prize (2014); OSA William F. Meggers Award (2012); IEEE Photonics Society William Streifer Scientific Achievement Award (2011); Rensselaer William H. Wiley 1866 Award (2009); Japan Society for the Promotion of Science Fellowship & NRC-CIAR Distinguished Visiting Scientist, Ottawa, Canada (2004); and First Heinrich Rudolf Hertz Lecturer, RWTH, Aachen, Germany (2003). He also served two years as a Distinguished Lecturer of IEEE/LEOS. He received Rensselaer Early Career Award (1996), Research Corporation Cottrell Scholar Award (1995), NSF Early Career Award (1995), K.C. Wong Prize, K.C. Wong Foundation, Hong Kong (1995), NSF Research Initiation Award (1992). In 1993–1994, he was an AFOSR-SRPF Fellow at Hanscom Air Force Base.

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Chen, Y.W., Zhang, XC. Anti-reflection implementations for terahertz waves. Front. Optoelectron. 7, 243–262 (2014).

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  • terahertz
  • anti-reflection
  • gradient index
  • photonic structure