Pitt physicists investigate light vortices in a new paper

Plasmonic vortices, which may have a role in formation of the structure of the universe, are the subject of an invited perspective published Jan. 6 by Pitt physicists in the journal ACS Photonics.

Led by Atreyie Ghosh, a graduate student in Professor Hrvoje Petek’s Laboratory of Ultrafast Dynamics, the paper looks at the current state of research and suggests a way to move forward and enhance the field’s understanding of fundamental physics of light.

Instead of the oscillating waves many of us are familiar with, structured light carrying spin and angular momentum can form vortex fields, where the electric and magnetic fields spin as stationary waves instead of propagating at the speed of light. These vortices are analogous to water flowing down a drain or a hurricane passing over oceans. In those cases, however, it is structured fluid — not light — forming the vortex.  

In the paper, the researchers considered the current methods of understanding certain properties of plasmonic vortices and outlined the ways some of them are inconsistent. Using analytic modeling, they were able to take the known data, including from their own research, and point in a direction that could lead to a consistent and robust classification of structure of vortices.

Petek’s lab researches vortex light and its role as a source of particles that are predicted by elementary particle theory to exist and to contribute to the fundamental structure of the universe.