Reconfigurable metamaterial components exploiting two-hot-arm electrothermal actuators

A tunable metamaterial, derived from the combination of two-hot-arm electrothermal actuators with a split-ring resonator, is introduced in this paper. Accomplishing a reliable control of the tip displacement, the selected set of radio-frequency microelectromechanical systems (RF-MEMS) circumvent the undesired bandwidth constraints of existing structures and establish significant levels of reconfigurability. To this objective, the aforementioned actuator is realized as an integrated part of the resonator, while a modified scheme for lower-frequency operation is also developed. Moreover, a double actuated device is proposed to further reduce the bias network complexity. A multiphysics analysis is conducted to reveal the characteristics of the associated RF-MEMS components prior embedding them to any complex medium. The featured designs are numerically verified through an assortment of setups, which utilize the finite element method to extract the constitutive parameters of the proposed metamaterials. Simulation data successfully prove their bandwidth enhancement capability, as well as the controllable mu-negative performance.