Category Physics

A team of University of Colorado Boulder engineers has developed a scalable manufactured metamaterial — an engineered material with extraordinary properties not found in nature — to act as a kind of air conditioning system for structures. It has the ability to cool objects even under direct sunlight with zero energy and water consumption.

University of Colorado Boulder engineers have developed a scalable manufactured metamaterial to act as a kind of air conditioning system for structures. It has the ability to cool objects even under direct sunlight with zero energy and water consumption...

The spin of the blue atoms differs from that of the red atoms. The laser beam shown in red thus only holds the red atoms, while the blue ones can be transported by the differently polarized laser beam to any position. (Image: Carsten Robens/Uni Bonn)

Physicists at the University of Bonn have cleared a further hurdle on the path to creating quantum computers: in a recent study, they present a method with which they can very quickly and precisely sort large numbers of atoms. Imagine you are standing in a grocery store buying apple juice. Unfortunately, all of the crates are half empty because other customers have removed individual bottles at random. So you carefully fill your crate bottle by bottle...

A layered ruthenate Ca2RuO4-y ceramic body contracts on heating, or exhibits negative thermal expansion (NTE). The sintered-body structure shows colossal NTE when extremely anisotropic thermal expansion of the crystal grains produces deformation, consuming open spaces (voids) on heating. The total volume change related to NTE reaches 6.7 percent at most, the largest reported so far. Credit: Koshi Takenaka

Machines and devices in modern industry are required to withstand harsh conditions. When environmental temperature changes, the volume of the materials used to make these devices usually changes slightly, typically by <0.01%. Although this may seem trivial, over time this thermal expansion can seriously degrade the performance of industrial systems and equipment.

Materials that contract o...

Array of low-power light-emitting diodes. Failure of a single LED does not affect the overall system. (Photo: KIT)

Researchers of Karlsruhe Institute of Technology (KIT) have developed a novel type of LED street light of increased efficiency. Compared to conventional LEDs, power consumption may be reduced by up to 20%. This will also decrease costs and CO2 emission. Conventional high-power diodes are replaced by a special array of LEDs. This enhances efficiency, increases service life and safety, and produces a better light.

Parallel connection of a large number of LEDs is difficult, as failure of a single diode will cause failure of the overall system or section...