Frontiers of Physics

, 14:42502 | Cite as

Time-resolved imaging of mode-conversion process of terahertz transients in subwavelength waveguides

  • Yao Lu
  • Qiang WuEmail author
  • Qi Zhang
  • Ri-De Wang
  • Bin ZhangEmail author
  • Wen-Juan Zhao
  • Deng Zhang
  • Hao Xiong
  • Cheng-Liang Yang
  • Ji-Wei Qi
  • Chong-Pei Pan
  • Jing-Jun Xu


We studied the mode-conversion process of terahertz pulses from a planar subwavelength waveguide to a tilted rectangular subwavelength waveguide. An unusual wavefront rotation, which led to an extra conversion time, was observed using a time-resolved imaging technique. We simulated the mode conversion process by a finite-difference time-domain method, and the results agreed well with the experiments. According to the simulations, the conversion time was demonstrated to become longer as the tilt angle or width of the rectangular waveguide increased. This work provides the possibility to optimize the future high-speed communications and terahertz integrated platforms.


ultrafast phenomenon mode conversion subwavelength waveguides terahertz waves 



This work was supported by the National Natural Science Foundation of China (NSFC) (Grant Nos. 61705013 and 61378018), the 111 Project (No. B07013), and the Program for Changjiang Scholars and Innovative Research Team in University (No. IRT 13R29).


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Copyright information

© Higher Education Press and Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  • Yao Lu
    • 1
  • Qiang Wu
    • 1
    Email author
  • Qi Zhang
    • 1
  • Ri-De Wang
    • 1
  • Bin Zhang
    • 2
    Email author
  • Wen-Juan Zhao
    • 1
  • Deng Zhang
    • 1
  • Hao Xiong
    • 1
  • Cheng-Liang Yang
    • 3
  • Ji-Wei Qi
    • 1
  • Chong-Pei Pan
    • 1
  • Jing-Jun Xu
    • 1
  1. 1.The Key Laboratory of Weak-Light Nonlinear Photonics, Ministry of Education, TEDA Institute of Applied Physics and School of PhysicsNankai UniversityTianjinChina
  2. 2.College of ScienceCivil Aviation University of ChinaTianjinChina
  3. 3.State Key Laboratory of Applied Optics, Changchun Institute of Optics, Fine Mechanics and PhysicsChinese Academy of SciencesChangchunChina

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