▎ 摘 要
Advanced metamaterials are designed upon the combination of (1) carbon nanotube (CNT) foam, which is obtained from chemical vapor deposition by fully consuming the initial nickel foam, and (2) nanosilver/silicone resin or graphene (Gr) foam. The CNT foam/nanosilver/silicone composite simultaneously exhibits a negative permittivity and permeability in the frequency range from 1 MHz to 1 GHz provided that the appropriate CNT foam amount is considered (20 m%). Double-negative performance in a similar frequency range is obtained with both 3/1 and 1/1 (mass basis) Gr/CNT-based composites. On the other hand, 3/2 (mass basis) Gr/CNT exhibits a negative permeability in the shared frequency range from 6 x 10(2) MHz to 1 GHz with still negative permittivity in the full range. The Gr amount allows to control the frequency behavior, with a variation in absolute permittivity and permeability values and a switch between a concave and convex behavior. Hence, the work contributes to the further expanding of the application range of metamaterials. [GRAPHICS]