The subject paper (Agrawal et al 2018 Mater. Res. Express 5, 115801) contains the incorrect assertion that both the effective relative permittivity and the effective relative permeability of an absorbing planar metamaterial structure can be purely real. The claim in the same paper that an optimized metamaterial structure is a broad-band absorber is also incorrect; instead, it is a broad-band linear-polarization converter.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Surfaces, Coatings and Films
- Polymers and Plastics
- Metals and Alloys