Metamaterials

[edit] Introduction

Metamaterials are composite media that can be engineered to exhibit properties that would not otherwise be naturally occurring in materials. The addition of the Greek prefix ‘meta’ (meaning beyond) implies that the substances exhibit properties that go beyond what would be typical.

Metamaterials are made up of nanoparticle building blocks (typically based on composite metals and plastics) that use extremely small, repetitive patterns to interact with light or other waves to produce dynamic effects. The refinement of the refraction can be modified to produce different values and transform positive refraction into negative.

[edit] Negative refraction

Negative refraction of light and other wave forms can be a highly desirable property. It bends waves as they enter the structure of the metamaterial, which may allow the materials to exhibit certain properties, including:

• Invisibility or optical camouflage.
• Extreme light magnification.
• Negative electrical permittivity and magnetic permeability.

[edit] Applications for metamaterials

Metamaterials capable of negative refraction may prove useful in the production of electronics, insulation and coating, heat transfer, energy harvesting and so on.

In the field of photovoltaics, some metamaterials can incorporate repetitive patterns to make better use of solar radiation. This could assist with the problem of silicon and other materials that demand certain cooling levels to maintain their efficiency. Their properties may enhance device light absorption while producing more electricity and improving efficiency through passive radiative cooling. .

Another such metamaterial is a type of sound control panel that uses acoustic metamaterials to make changes to audio waves. This type of product has the same noise reduction effect as conventional materials (such as plywood) but is significantly lighter. It bends sound waves to shape and control them.

[edit] Related articles on Designing Buildings

• Acoustic design for health and wellbeing.
• Building acoustics.
• Light.
• Phosphorescent building materials.
• Solar photovoltaics.
• Sonoblind.