Topological structure synthesized by three-dimensional spin angular momentum of light

Area of Science:

• Optics and Photonics
• Topological Physics
• Nanotechnology

Background:

• Hopf links are fundamental topological structures with applications across various scientific disciplines.
• Previous research demonstrated optical Hopf fibration textures by manipulating transverse polarization states and phase.
• Understanding and creating 3D topological structures in optics is an active area of research.

Purpose of the Study:

• To demonstrate the synthesis of Hopf links using three-dimensional spin angular momentum (3D SAM).
• To explore the manipulation of 3D polarization states within a tight focal volume.
• To showcase the creation of Hopf links with two and three linked circles.

Main Methods:

• Utilizing a 4Pi confocal optical system for tight focusing of complex optical fields.
• Employing 3D spin angular momentum (SAM) to manipulate the electric field's z-component.
• Synthesizing transverse and longitudinal polarization states within the focal volume.

Main Results:

• Successfully synthesized Hopf links through the manipulation of 3D SAM in a tightly focused optical system.
• Demonstrated the ability to control and engineer 3D polarization states, including the non-negligible z-component.
• Visualized examples of Hopf links comprising two and three disjoint and linked circles.

Conclusions:

• The study establishes a novel method for synthesizing Hopf links in 3D optical systems.
• The findings suggest potential applications in high-dimensional optical data storage and encryption.
• Hopf links synthesized via optical fields can serve as advanced information carriers.