English

Progress has been made in the research of phase modulation of terahertz programmable metasurfaces based on free carrier plasmonic dispersion effect

1088
2024-07-26 14:33:32
See translation

Recently, the team of Situ Guohai and Guo Jinying from the Aerospace Laser Technology and Systems Department of the Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, and the School of Microelectronics at Shanghai University collaborated to propose a terahertz phase controlled programmable metasurface design scheme based on free carrier plasma dispersion effect. The related research results were published in Applied Physics Letters under the title "Terahertz programmable metasurface for phase modulation based on free carrier plasma dispersion effect".

Terahertz modulators have broad application prospects in fields such as terahertz intelligent communication and computational imaging. However, existing terahertz phase modulators are not satisfactory in terms of speed, efficiency, and flux. Therefore, there is an urgent need to develop high-speed, efficient, and high-throughput terahertz spatial light modulators.

The research team proposed a terahertz programmable metasurface design scheme based on the free carrier plasmonic dispersion effect. By integrating the pn junction into the "H" - shaped metal metasurface unit structure and utilizing the change in external voltage to alter the carrier concentration distribution of the pn junction, continuous phase control at a frequency of 0.4 THz and 270 ° with an average efficiency of 30% were achieved in simulation. The metasurface unit adopts a "MIM" structure, and each unit is independently adjustable, while utilizing the high-speed switching characteristics of the pn junction, which is expected to achieve GHz level control speed. The team also demonstrated the far-field radiation results of the metasurface unit array, with a peak sidelobe ratio of 13dB, demonstrating excellent beam steering performance. The high-speed, efficient, and high-throughput advantages demonstrated by this design scheme in terahertz phase modulation are expected to play an important role in terahertz communication and imaging fields.

Figure 1. Schematic diagram of programmable metasurface unit structure and beam steering function

Figure 2. Continuous phase modulation of metasurface units under voltage

This research achievement has received support from the National Natural Science Foundation of China, the Shanghai Academic Research Leader Project, and the Shanghai Municipal Science and Technology Major Project.

Source: Shanghai Institute of Optics and Fine Mechanics

Related Recommendations
  • Application of Multipurpose Femtosecond Laser Interferometry in High Precision Silicon Nanostructures

    Researchers from the Laser Processing Group of the IO-CSIC Institute of Optics in Spain report on the application of multi-purpose femtosecond laser interference in high-precision silicon nanostructures. The related research was published in Optics&Laser Technology with the title "Versatile femtosecond laser interference pattern applied to high precision nanostructured of silicon".Highlights:...

    2024-07-10
    See translation
  • Devices based on optical thermodynamics can guide light without the need for switches

    Researchers from Ming Hsieh's Department of Electrical and Computer Engineering at the University of Southern California have designed the first optical device that follows the emerging optical thermodynamic framework.The work, reported in Nature Photonics, introduces a new way of routing light in nonlinear systems—meaning systems that do not require switches, external control, or digital addressi...

    10-15
    See translation
  • Laser company nLIGHT announces financial results for the second quarter of 2024

    Recently, nLIGHT, a manufacturer of high-power semiconductors and fiber lasers, announced its financial performance for the second quarter of 2024.According to the financial report, nLIGHT achieved a revenue of $50.5 million in the second quarter of 2024, a year-on-year decrease of 5.2% and an increase of 13% compared to the first quarter; The GAAP net loss for the second quarter was $11.7 million...

    2024-08-20
    See translation
  • An optical display technology based on mechanical optical mechanism

    The optical properties of afterglow luminescent particles in mechanical quenching and mechanical luminescence have aroused great interest in various technological applications. However, for specific photon applications, clearer explanations are needed for these unusual events.Recently, scientists from Pohang University of Science and Technology have designed an optical display technology with ALP ...

    2024-03-12
    See translation
  • Laser surface treatment of Ti6Al4V alloy: finite element prediction of melt pool morphology and microstructure evolution

    Researchers from the University of Calabria, University of Salento, and LUM University in Italy have reported on the progress of finite element prediction research on laser surface treatment of Ti6Al4V alloy: melt pool morphology and microstructure evolution. The related research was published in The International Journal of Advanced Manufacturing Technology under the title "Laser surface treatmen...

    04-10
    See translation