China Instrument Network Instrument R&D Recently, the Sheng Zhigao Group of the Strong Magnetic Field Science Center of the Chinese Academy of Sciences and the Dr. Jin Dingming, Ph.D., of Shanghai University, and Su Fuhai, a researcher of the Institute of Solid State Physics, Hefei Research Institute, have for the first time achieved graphene-based Terahertz stress modulators.
Terahertz stress modulator schematic
Terahertz (THz) generally refers to submillimeter electromagnetic waves with frequencies ranging from 1011 to 1013. Because of its superior spectral performance, terahertz-related technologies have a wide range of applications in areas such as communications, security, sensing, and national security, and are known as "one of the top ten technologies in the future." The terahertz modulator, which is a key component of the terahertz application, is an important subject for research in this field. In order to realize the modulation effect with high efficiency and low loss, in addition to traditional electrical and optical methods, obtaining a new terahertz modulation path is a scientific problem that needs urgently to be solved.
In this study, Dr. Sheng Zhigao's research group Dr. Zhilong built a stress modulation device based on two-dimensional electronic material, graphene, and systematically studied the stress of the device by using a self-built THz-TDS system. Modulation characteristics. Studies have shown that graphene-based devices have excellent modulation effects. The modulation depth is large, the modulation depth at 1THz is as high as 26%, and there is room for further improvement; bidirectional modulation is possible, and the terahertz wave modulation under tensile/compressive stress is positive/negative, respectively; the repeatability and stability are good. Thanks to the selected material - graphene has excellent mechanical and electrical properties; low insertion loss, stress-based terahertz modulation technology is mainly based on the regulation of intrinsic carrier mobility distribution, and there is no non-equilibrium carrier generation Therefore, it has far lower insertion loss than electrical and optical modulation. This regulation mechanism can be used to prepare high-speed terahertz modulators, and has a good development prospect in the future terahertz applications.
Related research results were published in "Advanced Optical Materials." This study was supported by the National Natural Science Foundation of China, the National Key Research and Development Program, the Frontier Science Key Research Project of the Chinese Academy of Sciences, and the “Thousand Talents Program for the Youthâ€.
(Original Title: Hefei Research Institute, etc. Made Progress in Terahertz Stress Modulator Research)