Researchers at Nanyang Technological University have turned to a 19th-century observation about the wave nature of light to produce optical skyrmions with striking simplicity. The work revives the Poisson spot, the bright centre that appears in the shadow of a small circular obstacle when illuminated by coherent light, and uses it to create multiple topological patterns simultaneously in a single light field.
This approach stands in contrast to earlier techniques that relied on intricate metamaterials or specialised laboratory setups. Instead, the team directed a laser at a modest circular disc. The resulting diffraction effect yielded up to four distinct varieties of optical skyrmion in one spot: spin, Stokes, electric-field and magnetic-field structures.
Optical skyrmions are stable, particle-like topological formations within the intensity, phase, polarisation, spin and field vectors of light. Their stability arises from mathematical properties that prevent them from unwinding easily, much like a knot that resists untying. Such features have long interested physicists exploring connections between light and other branches of physics, from particle theory to magnetic materials.
Assistant Professor Shen Yijie of Nanyang Technological University’s School of Physical and Mathematical Sciences and School of Electrical and Electronic Engineering led the effort. "What is remarkable is that optical skyrmions can now be generated using a simple effect where light bends around an object, without relying on expensive, complex man-made metamaterials or highly specialised techniques," he said.
The paper, titled Optical skyrmions in Poisson spots, appeared in Optica on 18 June 2026. A university announcement followed days later. The findings arrive at a time when photonics researchers seek more accessible routes to study these exotic light structures.
What is remarkable is that optical skyrmions can now be generated using a simple effect where light bends around an object, without relying on expensive, complex man-made metamaterials or highly specialised techniques.
Shen emphasised the practical shift. "This could make optical skyrmions much more accessible to researchers. By lowering the technical barrier to creating and studying them, the method opens up new possibilities for scientists to study how they could be used in future optical, materials and computing research."
