PhysOrg General Physics - 03 June 2010
Scientists from China have built a device that can trap and absorb microwaves coming from all directions with a 99% absorption rate - a property that makes the device simulate, to some extent, an astrophysical black hole.
...
The device itself is composed of a thin cylinder containing 60 concentric rings of copper-coated metamaterials arranged in layers. Each layer is imprinted with alternating patterns of resonant and non-resonant metamaterial structures. The design traps and absorbs microwaves coming from all directions by spiraling the radiation inward and converting its energy into heat. As with a black hole, electromagnetic radiation cannot escape from the device.
(Left) A model of the electromagnetic omnidirectional absorber, in which electromagnetic waves hitting the cylinder bend spirally in the shell region, and become trapped and absorbed by the lossy core. (Right) A photograph of the device, which is composed of 60 concentric layers of copper-coated metamaterials. (Institute of Physics)
An omnidirectional electromagnetic absorber made of metamaterials
- New Journal of Physics 12 063006 (June 2010). DOI: 10.1088/1367-2630/12/6/063006.
