Dynamically-adjustable multi-frequency electromagnetic wave-absorbing material

Abstract

The present invention provides a dynamically-adjustable multi-frequency electromagnetic wave-absorbing material. The material comprises, in turn from bottom to top, an underlying metal reflective layer, a dielectric spacer layer and a top metal sub-wavelength structure array. The material for the dielectric spacer layer is a GST phase change material. In the invention, the crystalline state (phase) of the GST material is changed by means of electrical excitation, optical excitation or thermal excitation and thus optical parameters of the GST material, such as a dielectric constant, are changed, so multi-band absorption of the wave-absorbing material within the infrared range and dynamic modulation of the wave-absorbing frequency band are realized, thereby improving the flexibility of the wave-absorbing material. In addition, the present invention can also realize a conformal design with a complex face object.

Description

technical field [0001] The invention belongs to the field of electromagnetic wave absorption, in particular to a dynamically adjustable multi-frequency electromagnetic wave absorbing material. Background technique [0002] The electromagnetic response characteristics of traditional absorbing materials depend on the properties of the material's own atoms and molecules, so there are still some defects that are difficult to overcome, such as narrow absorption bandwidth, high density, and poor environmental adaptability. With the requirement of equipment concealment in some application fields, there is an urgent demand for the miniaturization, planarization and integration of the absorber. Artificially structured materials have attracted increasing attention due to their exotic electromagnetic response properties, including artificial magnetic properties, negative magnetic permeability, negative refractive index, and hyperbolic dispersion. These artificial structural materials ...

AI Technical Summary

Problems solved by technology

When the temperature is lower than the phase transition temperature, VO 2 Acting as a dielectric layer in the structure can make the structure effectively absorb electromagnetic waves; however, when the temperature is close to or higher than the phase transition temperature, VO 2 Gradually turned into a metal, the absorption effect of the structure becomes significantly worse, and because the VO 2 The phase transition temperature is low, this material is easily affected by the environment, it is not suitable for tunable absorption in complex environments, and its excitation method is limited to thermal excitation

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