Photonic crystals tagged posts

Dr. Jin Gu, Kang and his team at the Nanophotonics Research Center at the Korea Institute of Science and Technology (KIST) have developed a colorful radiation-cooling liquid crystal material that can cool without external power while simultaneously emitting color. The work is published in the Chemical Engineering Journal.

Radiative cooling is a powerless cooling technology that releases infrared radiation as heat throug...

This is the directional emission of light. Credit: TU Wien

Recently, surprising physical effects were observed using special microscopic waveguides for light. Such “photonic structures” currently are revolutionizing the fields of optics and photonics, and have opened up the new research area of “Chiral Quantum Optics.” What one learns at school is that light oscillates under a right angle (transversal) with respect to its direction of propagation. Among experts, however, it was already known that light behaves differently when it is confined strongly in the transversal plane using “photonic structures.” In particular, this is the case for special ultra-thin glass fibers which have a diameter of only a few hundred nanometers and which are thereby smaller than the wavelength of light...

This image shows theoretical (right) and experimental (left) iso-frequency contours of a photonic crystal slabs superimposed on each other. Credit: Massachusetts Institute of Technology

A new technique developed by MIT researchers reveals the inner details of photonic crystals, synthetic materials whose exotic optical properties are the subject of widespread research. Photonic crystals are generally made by drilling millions of closely spaced, minuscule holes in a slab of transparent material, using variations of microchip-fabrication methods...

A team of physicists that visualized the internal nanostructure of an intact butterfly wing has discovered two physical attributes that make those structures so bright and colorful. Credit: © boule1301 / Fotolia

A team of physicists that visualized the internal nanostructure of an intact butterfly wing has discovered 2 physical attributes that make those structures so bright and colorful. “Over millions of years, butterflies have evolved sophisticated cellular mechanisms to grow brightly colored structures, normally for the purpose of camouflage as well as mating,” says A/prof Oleg Shpyrko, Physics, UC SD. “It’s been known for a century that the wings of these beautiful creatures contain what are called photonic crystals, which can reflect light of only a particular color.”

But exactly ho...