An electrically tunable absorbing metasurface for surface waves and plane waves

When illuminated by high power microwaves, electronic devices are usually suffered from energy that leaks inside through inevitable gaps or cracks on the metallic shells. To solve this issue, an absorbing metasurface that is effective for both surface waves and plane waves is proposed. Owing to the varactor diodes and biasing circuits embedded in the lattice structure, the absorption rate can be tuned with a large range by varying direct current biasing voltage. These performances are demonstrated by simulations and measurements. If incorporating with integrated-circuit sensors, the absorbing properties could potentially be extended. For example, they could be tuned in response to environmental variables, such as microwave power, light, or pressure, and thus lead to varieties of applications.