中国物理B ›› 2019, Vol. 28 ›› Issue (11): 118502-118502.doi: 10.1088/1674-1056/ab44ac

• INTERDISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY • 上一篇    下一篇

The origin of distorted intensity pattern sensed by a lens and antenna coupled AlGaN/GaN-HEMT terahertz detector

Xiang Li(李想), Jian-Dong Sun(孙建东), Hong-Juan Huang(黄宏娟), Zhi-Peng Zhang(张志鹏), Lin Jin(靳琳), Yun-Fei Sun(孙云飞), V V Popov, Hua Qin(秦华)   

  1. 1 Key Laboratory of Nanodevices and Applications, Suzhou Institute of Nano-tech and Nano-bionics, Chinese Academy of Sciences, Suzhou 215123, China;
    2 School of Nano Technology and Nano Bionics, University of Science and Technology of China, Hefei 230026, China;
    3 Nanofabrication Facility of the Suzhou Institute of Nano-tech and Nano-bionics, Chinese Academy of Sciences, Suzhou 215123, China;
    4 College of Electronic and Information Engineering, Suzhou University of Sciences and Technology, Suzhou 215009, China;
    5 Kotelnikov Institute of Radio Engineering and Electronics, Saratov Branch, Russian Academy of Sciences, Saratov 410019, Russia
  • 收稿日期:2019-05-30 修回日期:2019-08-30 出版日期:2019-11-05 发布日期:2019-11-05
  • 通讯作者: Jian-Dong Sun, Hua Qin E-mail:jdsun2008@sinano.ac.cn;hqin2007@sinano.ac.cn
  • 基金资助:
    Project supported by the National Key Research and Development Program of China (Grant No. 2016YFF0100501), the National Natural Science Foundation of China (Grant Nos. 61771466, 61775231, and 61611530708), the Six Talent Peaks Project of Jiangsu Province, China (Grant No. XXRJ-079), the Youth Innovation Promotion Association of Chinese Academy of Sciences (Grant No. 2017372), the Russian Foundation for Basic Research (Grant No. 17-52-53063), and the Natural Science Foundation of Jiangsu Province, China (Grant No. BK20160400).

The origin of distorted intensity pattern sensed by a lens and antenna coupled AlGaN/GaN-HEMT terahertz detector

Xiang Li(李想)1,2, Jian-Dong Sun(孙建东)1, Hong-Juan Huang(黄宏娟)3, Zhi-Peng Zhang(张志鹏)1, Lin Jin(靳琳)1, Yun-Fei Sun(孙云飞)4, V V Popov5, Hua Qin(秦华)1   

  1. 1 Key Laboratory of Nanodevices and Applications, Suzhou Institute of Nano-tech and Nano-bionics, Chinese Academy of Sciences, Suzhou 215123, China;
    2 School of Nano Technology and Nano Bionics, University of Science and Technology of China, Hefei 230026, China;
    3 Nanofabrication Facility of the Suzhou Institute of Nano-tech and Nano-bionics, Chinese Academy of Sciences, Suzhou 215123, China;
    4 College of Electronic and Information Engineering, Suzhou University of Sciences and Technology, Suzhou 215009, China;
    5 Kotelnikov Institute of Radio Engineering and Electronics, Saratov Branch, Russian Academy of Sciences, Saratov 410019, Russia
  • Received:2019-05-30 Revised:2019-08-30 Online:2019-11-05 Published:2019-11-05
  • Contact: Jian-Dong Sun, Hua Qin E-mail:jdsun2008@sinano.ac.cn;hqin2007@sinano.ac.cn
  • Supported by:
    Project supported by the National Key Research and Development Program of China (Grant No. 2016YFF0100501), the National Natural Science Foundation of China (Grant Nos. 61771466, 61775231, and 61611530708), the Six Talent Peaks Project of Jiangsu Province, China (Grant No. XXRJ-079), the Youth Innovation Promotion Association of Chinese Academy of Sciences (Grant No. 2017372), the Russian Foundation for Basic Research (Grant No. 17-52-53063), and the Natural Science Foundation of Jiangsu Province, China (Grant No. BK20160400).

摘要: Antenna-coupled field-effect-transistors (FETs) offer high sensitivity for terahertz detection. Both the magnitude and the polarity of the response signal are sensitive to the localized terahertz field under the gate. The ability of accurate sensing the intensity pattern is required for terahertz imaging systems. Here, we report artefacts in the intensity pattern of a focused terahertz beam around 1 THz by scanning a silicon-lens and antenna coupled AlGaN/GaN high-electron-mobility-transistor (HEMT) detector. The origin of the image distortion is found to be connected with one of the antenna blocks by probing the localized photocurrents as a function of the beam location and the frequency. Although the exact distortion is found with our specific antenna design, we believe similar artefacts could be commonplace in antenna-coupled FET terahertz detectors when the beam spot becomes comparable with the antenna size. To eliminate such artefacts, new antenna designs are welcomed to achieve strong asymmetry in the terahertz field distribution under the gate while maintaining a more symmetric radiation pattern for the whole antenna.

关键词: terahertz detector, self-mixing, high electron mobility transistor, local electrical field

Abstract: Antenna-coupled field-effect-transistors (FETs) offer high sensitivity for terahertz detection. Both the magnitude and the polarity of the response signal are sensitive to the localized terahertz field under the gate. The ability of accurate sensing the intensity pattern is required for terahertz imaging systems. Here, we report artefacts in the intensity pattern of a focused terahertz beam around 1 THz by scanning a silicon-lens and antenna coupled AlGaN/GaN high-electron-mobility-transistor (HEMT) detector. The origin of the image distortion is found to be connected with one of the antenna blocks by probing the localized photocurrents as a function of the beam location and the frequency. Although the exact distortion is found with our specific antenna design, we believe similar artefacts could be commonplace in antenna-coupled FET terahertz detectors when the beam spot becomes comparable with the antenna size. To eliminate such artefacts, new antenna designs are welcomed to achieve strong asymmetry in the terahertz field distribution under the gate while maintaining a more symmetric radiation pattern for the whole antenna.

Key words: terahertz detector, self-mixing, high electron mobility transistor, local electrical field

中图分类号:  (Photodetectors (including infrared and CCD detectors))

  • 85.60.Gz
72.80.Ey (III-V and II-VI semiconductors) 84.40.Ba (Antennas: theory, components and accessories)