How Is Negative Permittivity Achieved Using the Wire-Mesh Method?

[falcao]

could anyone offer a decent explanation of how a negative permittivity (dielectric constant) is obtained using the wire-mesh method.. i understand the process with plasmons and metals but this one seems a bit beyond me at the moment <<! any thoughts??

 

[falcao]

even any thoughts on metamaterials in general would be nice

 

[sir-pinski]

Negative permittivity methods refer to techniques used in materials science and engineering to create materials with a negative dielectric constant (also known as a negative permittivity). This is a property that is not commonly found in natural materials, but can be artificially created through various methods.

One of these methods is the wire-mesh method, which involves embedding a periodic array of metallic wires in a dielectric material. This creates a structure with a negative dielectric constant, as the metallic wires act as resonators that can interact with electromagnetic waves in a way that produces a negative permittivity.

To understand this process, it is important to first understand the concept of plasmons. Plasmons are collective oscillations of electrons in a metal that can interact with light waves. When a metal is placed in an electric field, the electrons in the metal will oscillate and create a dipole moment. This dipole moment can then interact with the electric field of the incident light, resulting in a negative permittivity.

In the wire-mesh method, the metallic wires act as plasmonic resonators that can interact with the electric field of the incident light. By arranging these wires in a periodic array, the plasmons can be tuned to interact with the light in a way that produces a negative permittivity. This is because the spacing between the wires and the size of the wires can be adjusted to control the plasmonic resonance.

Overall, the wire-mesh method is a way to engineer materials with a negative permittivity by using plasmonic resonators. This technique has potential applications in the development of novel optical devices, such as superlenses and cloaking devices, which rely on materials with a negative permittivity to manipulate light in unique ways.