A transmissive terahertz wave encoder and encoding system based on plasma devices

Abstract

The invention discloses a transmission-type terahertz wave encoder based on plasma device, and an encoding system. The encoder comprises a silicon base and a two-dimensional array with a top surface formed by N*N square unit structures; each unit structure comprises a metal structure aligned with a center, namely, the U-shaped structure and a l-shaped structure at the right side thereof to parallel to the vertical part, and the transverse median lines of the U-shaped structure and the l-shaped structure are aligned. The terahertz encoder is between the encoding system terahertz and a receiver,the encoder is arranged on a sample holder capable of rotating around Y and Z-axle; the terahertz polarizes along the X-axle and propagates along the Z-axle. The encoder two-dimensional array faces the terahertz source. The resonance characteristic of the surface plasma excimer in the encoder is changed when the relative angle of the encoder and the terahertz optical shaft or polarization direction is changed, the transmissivity of the dual-band is independently controlled, and the binary encoding of the dual-band terahertz is realized. The encoder is single in structure and easy to manufacture; the system is convenient for operation and strong in practicability.

Description

technical field [0001] The invention relates to the technical field of terahertz wave encoders, in particular to a transmission type terahertz wave encoder and an encoding system based on a plasma device. Background technique [0002] Plasma devices, also known as micro-nano structure devices, are a new type of sub-wavelength artificial metal structure materials, which can bind electromagnetic fields on metal surfaces, excite collective oscillations of electrons, form surface plasmons, and utilize surface plasmons Electromagnetic waves are modulated by the interaction of excitons with incident electromagnetic fields. Plasmonic devices can be realized with simple structures, typically metal unit structures arranged periodically on a dielectric substrate, where each metal unit structure has a pore structure or strip structure in the sub-wavelength scale range. The frequency of the surface plasmons excited by the array structure composed of each unit structure is highly depend...

AI Technical Summary

Problems solved by technology

However, the existing terahertz encoders are not only complicated in design and cumbersome in the processing process, but also the direction of the emitted terahertz waves after passing through these encoders is not unique, which leads to the need to constantly adjust the optical path in the actual detection of the terahertz time-domain spectroscopy system. receiver position to receive the signal

Because terahertz waves are invisible light waves, it is very difficult to adjust the experimental optical path of the terahertz time-domain spectroscopy system to achieve collimation and confocality, so the practicability of existing terahertz encoders is greatly limited

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