What is a Hyperlens?
hyperlens (plural hyperlenses) (optics) A nanostructured metamaterial that produces magnified images of objects smaller than the wavelength of the light used.
How does a Metalens work?
A metalens is made by depositing an array of subwavelength “pillars” of a high-index material on a flat substrate on the order of a millimeter thick, with both materials transparent at the transmitted wavelength.
Which materials offer the potential to create superlenses?
Metamaterials offer the potential to create superlenses.
How does a Superlens work?
Superlensing results from the enhancement of evanescent waves by surface plasmons. The key to the superlens is its ability to significantly enhance and recover the evanescent waves that carry information at very small scales. This enables imaging well below the diffraction limit.
Is negative refraction possible?
Negative refraction occurs at interfaces between materials at which one has an ordinary positive phase velocity (i.e., a positive refractive index), and the other has the more exotic negative phase velocity (a negative refractive index).
How do metasurfaces work?
The principle of operation of metasurfaces is based on the phenomenon of diffraction. Any flat periodic array can be viewed as a diffraction lattice, which splits the incident light into a few rays.
What is a Metasurface lens?
Metasurfaces, the corresponding two-dimensional metamaterials, can flexibly control the amplitude, phase, and polarization of light through sub-wavelength units, compared with the traditional lens that relies on the modulated light beam to accumulates the phase delay during the transmission, it is smaller in size.
What is chiral metamaterial?
Chiral metamaterials generally consist of arrays of planar metallic or dielectric gammadions on a substrate, where, if linearly polarized electromagnetic wave such as GHz, THz, or visible light is incident on the array, it becomes elliptically polarized upon interaction with the gammadions with the same handedness as …
Why is metasurface important?
One of the most important applications of metasurfaces is to control a wavefront of electromagnetic waves by imparting local, gradient phase shifts to the incoming waves, which leads to a generalization of the ancient laws of reflection and refraction.
What is meant by negative refractive index?
A negative refractive index implies that the phase of a wave decreases rather than advances with passage through the medium. As Veselago pointed out, this fundamental reversal of wave propagation contains important implications for nearly all electromagnetic phenomena.
What happens if refractive index is negative?
What happens when refractive index 0?
When the refractive index is reduced to zero the light no longer behaves as a moving wave, traveling through space in a series of crests and troughs, otherwise known as phases. Instead, the wave is stretched infinitely long, creating a constant phase.