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Updated: Nov 5, 2025
13:39
Optical Trapping of Nanoparticles
Published on: January 15, 2013
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Optical grinder: sorting of trapped particles by orbital angular momentum
Optics Express
|May 14, 2021
Summary
We developed a tunable light field using orbital angular momentum (OAM) beams to precisely manipulate and sort microparticles. This optical grinding technique allows for size-based separation of dielectric spheres and yeast cells.
Area of Science:
- Optics and Photonics
- Optical Manipulation
- Microparticle Sorting
Background:
- Orbital angular momentum (OAM) beams offer unique light field structures.
- Advanced optical manipulation requires precise control over light-matter interactions.
Purpose of the Study:
- To create a tunable light landscape for advanced optical manipulation.
- To demonstrate size-based sorting of microparticles using OAM beams.
Main Methods:
- Customized transversely structured light fields using Laguerre-Gaussian (LG) modes with opposite OAM handedness.
- Generated counter-rotating OAM transfer in a concentric intensity structure.
- Utilized the light field's tunability via LG mode indices.
Main Results:
- Demonstrated trapping and rotation of silica spheres of various sizes.
- Achieved spatial separation of trapped objects based on their size.
- Showcased on-demand tuning of trapping potential and sorting criteria.
- Successfully discriminated between yeast cells and silica spheres by size.
Conclusions:
- The developed OAM-based light field provides a versatile tool for optical manipulation and sorting.
- The approach is adaptable for tuning trapping potentials and sorting criteria.
- The method shows potential for biomedical applications, including cell and particle discrimination.
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