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ELEKTRO 11/2016 was released on November 7th 2016. Its digital version will be available on December 1st 2016.

 

Topic: Switchboards and switchboard engineering; Rotating electrical machines and power electronics; Maintenance of EE

 

Main Article

Lithium traction batteries for electric mobility (part 1)

SVĚTLO (Light) 6/2016 was released on December 5th 2016. Its digital version will be available on January 5th 2017.

Interiors lighting
Colloquium Interiors 2016 – the fifth anniversary
Cooperation of indoor interior and lighting 

Standards, regulations and recommendations
New standards for road lighting

Physicists discover a new form of light

18.05.2016 | Trinity College Dublin | www.tcd.ie

Physicists from Trinity College Dublin’s School of Physics and the CRANN Institute, Trinity College, have discovered a new form of light, which will impact our understanding of the fundamental nature of light.

One of the measurable characteristics of a beam of light is known as angular momentum. Until now, it was thought that in all forms of light the angular momentum would be a multiple of Planck’s constant (the physical constant that sets the scale of quantum effects).

Discovery of new type of light

Now, recent PhD graduate Kyle Ballantine and Professor Paul Eastham, both from Trinity College Dublin’s School of Physics, along with Professor John Donegan from CRANN, have demonstrated a new form of light where the angular momentum of each photon (a particle of visible light) takes only half of this value. This difference, though small, is profound.

To make this discovery, the team used an effect discovered in the 1830s by mathematician William Rowan Hamilton and physicist Humphrey Lloyd who found that, upon passing through certain crystals, a ray of light became a hollow cylinder. The team used this phenomenon to generate beams of light with a screw-like structure.

Analysing these beams within the theory of quantum mechanics they predicted that the angular momentum of the photon would be half-integer, and devised an experiment to test their prediction. Using a specially constructed device they were able to measure the flow of angular momentum in a beam of light.

Read more at Trinity College Dublin

Image Credit: Adobe Stock

-jk-