Dual-tunable metamaterial absorber based on solid ion gel-graphene sandwich structure

摘要

Electrically tunable metamaterial is attracting extensive attention recently for its potential in electromagnetic compatibility (EMC) and radar scattering manipulation, while still remains a great deal of challenges in its tunability. In this paper, a conductivity tunable graphene-ion gel-graphene (GIG) sandwich structure is fabricated and measured to investigate the properties of ion gel. showing its advantages over ion liquid on flexibility and tunability. Besides, a frequency and amplitude dual-tunable metamaterial absorber based on the GIG sandwich structure is proposed, modeled and optimized. From the simulated response, the absorber can achieve the tuning of absorption frequency from 5.4 GHz to 7.1 GHz and the reflection minimum from -15 dB to -45 dB. With the introduction of tunability from varactor diodes and graphene. the working frequency and absorption can be almost independently tuned. This work gives a meaningful reference for graphene based tunable metamaterial based on solid ion gel. especially in conformal and outdoor environment applications.