Physicists discover a new form of light

 

International Conference on Condensed Matter Physics

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).
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. These results were recently published in the online journal Science Advances.

Commenting on their work, Assistant Professor Paul Eastham said: "We're interested in finding out how we can change the way light behaves, and how that could be useful. What I think is so exciting about this result is that even this fundamental property of light, that physicists have always thought was fixed, can be changed."

Theoretical physicists since the 1980s have speculated how quantum mechanics works for particles that are free to move in only two of the three dimensions of space. They discovered that this would enable strange new possibilities, including particles whose quantum numbers were fractions of those expected. This work shows, for the first time, that these speculations can be realised with light.

#physics #light #science #discovery #innovation



Comments

Post a Comment

Popular posts from this blog

A new way to create a crystalline structure called a “density wave”

Image
  A density wave (DW) is a fundamental type of long-range order in quantum matter tied to self-organization into a crystalline structure. Although density waves are seen in a wide range of materials, such as metals, insulators, and superconductors, studying them has proven challenging, particularly when this order (the patterns of the wave’s particles) coexists with other types of organization, such as superfluidity, which allows particles to flow without resistance. Scientists at EPFL have found a new way to create a “density wave” in an atomic gas. The findings could lead to a better understanding of the behavior of quantum matter. Professor Jean-Philippe Brantut at EPFL said, “Cold atomic gases were well known in the past for the ability to ‘program’ the interactions between atoms. Our experiment doubles this ability!” To study this interaction, Brantut, and his colleagues created a “unitary Fermi gas,” a thin gas of lithium atoms that has been cooled to incredibly low temperatu...
Read more

New hydrodynamic theory helps to understand the correlation of ions

Image
  In their theoretical work, Dr. Diddo Diddens from Helmholtz Institute Münster of Forschungszentrum Jülich and Prof. Andreas Heuer from the Helmholtz Institute Münster and the Institute of Physical Chemistry of the University of Münster investigated the central question of the extent to which ions in liquid electrolytes move statistically correlated, i.e. together, in one direction. With this knowledge, the influence of individual factors, such as ion pairs on conductivity, can be better determined. The detailed results of their study have been published in the Journal of Chemical Physics and on the pre-print server arXiv. It is often assumed that two ions with the same charge avoid each other due to mutual repulsion and thus move in opposite directions. Now, the researchers are able to show that two neighboring ions with the same charge move in the same direction. "This counter-intuitive behavior can be explained by the fact that the electrolyte, as a liquid, is incompressible, ...
Read more

'Einstein Was Right: You Can Turn Energy Into Matter'

Image
  International Conference on Condensed Matter Physics E=mc2 Albert Einstein proposed the most famous formula in physics in a 1905 paper on Special Relativity titled Does the inertia of an object depend upon its energy content? Essentially, the equation says that mass and energy are intimately related. Atom bombs and nuclear reactors are practical examples of the formula working in one direction, turning matter into energy. But until now there has been no way to do the reverse, turn energy into matter. What makes it particularly hard is that c2 term, the speed of light squared. It accounts for the huge amounts of energy released in nuclear reactions, and the huge amount you’d need to inject to turn energy into matter. Previous experiments have always required a little bit of mass, even if it was only an electron’s worth. But scientists at Imperial College London (including a visiting physicist from Germany's Max Planck Institute for Nuclear Physics) think they’ve figured out how to...
Read more