Revolutionary devices that can get around the diffraction limit include so-called superlenses made from metamaterials with negative refraction
indices that bend light in an opposite sense to conventional materials.
There are two kinds of imaging based on negative refraction
for PC, one is near field imaging and
Applications such as photonic crystals for visible wavelength biosensors, optical-wavelength metamaterials showing negative refraction
both require sub 100-nm resolution.
Metamaterials (MMs) have gained plenty of attention during the past few years for its exotic properties, such as perfect lens , negative refraction
, filters  and cloaks [4, 5], which can be seldom achieved by traditional materials.
Veselago in detail studied the interesting property of negative refraction
in left handed materials .
The results can be utilized for realization of a helical array metamaterial which has demonstrated the negative refraction
This edition has been updated with new examples, exercises, and sections on optical control of spin, quantum dots, diamond NV centers, carbon nanostructures, negative refraction
, and plasmonics.
His theoretical research speculated on a material that was "tuned" using electronic components to manipulate its electric and magnetic properties, thereby producing a negative refraction
R produces a variety of very specialized structures reflecting different colors (structural colors--photonic crystals--on butterfly wings) and in general different wavelengths (UV: communication, NIR: thermoregulation), broad-band reflectors, dynamic color changes (chameleon) antireflectmg surfaces (transparent moth wings and eyes) and even negative refraction
Metamaterials that achieve negative refraction
are called negative index materials, or NIMs.
Previous research has demonstrated negative refraction
with invisible microwaves.
We found that at a particular wave frequency the meta-material has a negative refraction
effect, which means that the image produced in the flat lens appears at a high resolution in exactly the same way it appears in reality," Guenneau said.