Fig. 1.

Decoupled modulation of reflection amplitude and phase. a–c Schematic diagram of holey lossy metamaterials with an absorbing boundary at the back side in a, three-dimensional (3D) illustration in b and cross-section view of a unit cell in c are appended. d–g The coupling coefficients ${\overline{M}}_{A\left(\varphi \right),h_1\left(w\right)}$ vs. h and β with decoupled points (DPs) and quasi-DPs marked by the crosses and arrows, respectively. h, i The reflection amplitude and phase responses to the parameters h₁ and w for a unit cell operating at quasi-DPs. j, k The simulated and measured amplitude and phase vs. w and h₁, respectively, which reveals that the reflection amplitude and phase are controlled by only one parameter, respectively. The simulations are carried out by the finite element solver in commercial software COMSOL Multiphysics^TM5.0