| Popis: |
Metamaterials allow for the creation of electromagnetic media with properties that are not found in or, are much weaker in, natural materials. The authors discuss design methods to minimize dissipative loss and the use of gain to compensate dissipation. Returning to the loss problem, there are basically three approaches that we can follow to reduce the impact of dissipative loss in metamaterials: Use better constituent materials. This is considered here, where the authors discuss a model to compare different conducting materials, including graphene at optical frequencies, transparent conducting oxides, noble metals and alkali metals. Pursue passive reduction of dissipation, i.e. optimize the geometry of meta-atoms to minimize dissipation loss. A few methods to achieve this is discussed here. Introduce gain in the meta-atoms to counteract the dissipation. |
