Concentric ring optical traps for orbital rotation of particles

Area of Science:

• Optics and Photonics
• Optical Manipulation
• Microscopy and Imaging

Background:

• Optical vortices (OVs) are essential for particle micro-manipulation.
• Perfect optical vortices (POVs) offer topological charge-independent vortex radius, enhancing optical trapping.
• Existing methods require further development for complex particle manipulation tasks.

Purpose of the Study:

• To introduce and characterize concentric ring optical traps (CROTs).
• To demonstrate the application of CROTs in trapping and rotating multiple particles.
• To explore the potential of CROTs in advanced optical manipulation applications.

Main Methods:

• Theoretical proposal and numerical simulation of CROTs.
• Experimental generation and characterization of CROTs using optical setups.
• Demonstration of trapping and rotating dielectric and gold particles.

Main Results:

• CROTs exhibit weak sidelobes, good uniformity, and high diffraction efficiency.
• Simultaneous trapping and rotation of multiple dielectric particles on different rings achieved.
• Controlled rotation of particles based on the topological charge of individual rings.

Conclusions:

• CROTs represent a novel and versatile tool for optical trapping and manipulation.
• The independent control of radius and topological charge in CROTs allows for complex particle manipulation.
• CROTs show promise for applications in microfluidics and advanced optical studies.