Microwave metamaterial absorber based on aqueous electrolyte solution for X-band application

摘要

Metamaterial absorber is investigated by using an aqueous electrolyte solution as a meta-"atom." For the first time, an aqueous electrolyte solution of Aluminum Chloride (AlCl3) is used as a fluid filler for a periodic rectangular metastructure. Aqueous solutions of varying molarity (0.5, 1.0, 1.5, 2.0, and 2.5M) are encapsulated inside a flexible silicone rubber sheet to develop a meta-"atom" and realized as a resonating microwave metamaterial absorber backed with copper. The complex material permittivities of the electrolyte solutions are measured at an X-band (8.2-12.4 GHz) frequency region. A unit cell is designed and its parameters are optimized in a computer simulation software microwave studio suite to enhance a wide absorption bandwidth with 90% absorption efficiency throughout the X-band region. Additionally, the proposed absorber shows a polarization insensitive absorption along with a wide-incident angle absorption for both TM and TE waves. The resonance and absorption mechanisms are investigated with the help of electric field, magnetic field, current density and penetration depth of microwave into the electrolyte solution. The experimental absorption performance is carried out in an ideal waveguide environment. Published under license by AIP Publishing.