Physicists created and detected Skyrmions after they constructed a topological model of these elusive fundamental particle in a light beam.
Professor Janne Ruostekoski from Lancaster University collaborated with researchers from the University of Birmingham, Riken in Japan and Muenster in Germany to construct a theoretical model where light forms a localised particle-like knotted object in space.
The proposed light particle was then experimentally created and measured in a laboratory in Muenster.
Their research is published in Nature Communications.
This topological model of a particle for a light beam is reminiscent of theoretical models of elusive elementary particles predicted 60 years ago when Professor Tony Skyrme, a mathematical physicist at the University of Birmingham, developed a system to demonstrate Skyrmion's behavior. His system used the structure of spheres in 4-dimensional space to guarantee the indivisible nature of this elusive kind of fundamental particle in 3 dimensions.
Three-dimensional (3D) topological states resemble truly localized, particle-like objects in physical space. They even have gathered scientists' attention as exotic textures in particle physics, cosmology, superfluids, and many other systems.
3D particle-like Skyrmions have been investigated for over 50 years. However, despite this fact, 3D Skyrmions have been seen very rarely in experiments. The most current research into Skyrmions focuses on 2D analogs, which shows promise for new technologies.
The researchers created the model by casting the standard description of light: polarization and phase- in terms of a sphere in 4-dimensional space, crucial to Skyrme's original vision. This allowed them to design and engineer the Skyrmion field into a beam of laser light. Using advanced measurements, they determined the precise structure of the Skyrmion.
Professor Mark Dennis from the University of Birmingham said: "Skyrmions have intrigued and challenged physicists for many decades. Although we're making good progress investigating Skyrmions in 2D, we live in a 3D world. We need a system that can model a Skyrmion in all its possible states in a way that could be measured. We realized that a beam of light could be harnessed for this purpose because we can closely control its properties and so use it as a platform to model our Skyrmions. With this approach, we can start to understand these objects and realize their scientific potential truly."
