A team of physicists from Trinity College , Dublin (Ireland) has discovered a new form of light where the angular momentum of each photon, that is, one of the measurable characteristics of a beam of light, is barely half of the physical constant that establishes the scale of the quantum effects, the Planck constant and not a multiple of it as until now it was believed to occur in all forms of light. This discovery will mark a new step in our understanding of the fundamental nature of light.
“We are interested in how we can change the way light behaves, and how it could be useful. What I think is so exciting about this result is that even this fundamental property of light, which physicists have always thought was stable , can change, ”explains study leader Paul Eastham.
To reach this milestone in physics, the scientists used an effect in which a beam of light as it passes through certain crystals turns into a hollow cylinder , creating bolt-like beams of light. By analyzing these beams of light within the theory of quantum mechanics, they were able to measure the flux of angular momentum in a beam of light and measure the variations in this flux caused by quantum effects.
The results of the experiment revealed a change, small, yes, but important: the value of each photon in the angular momentum was half of Planck’s constant, which implies new possibilities within quantum mechanics about what we can arrive at perform with light, as theoretical physicists had speculated in the 1980s.
The conclusions of the study have been published in the journal Science Advances.




