Optical tweezing using tunable optical lattices along a few-mode silicon waveguide.

Area of Science:

• Photonics
• Nanotechnology
• Biophysics

Background:

• Optical lattices and holographic tweezers revolutionized particle manipulation.
• Near-field optical forces are crucial for trapping diverse objects in integrated devices.
• On-chip manipulation of multiple objects using guided light remains challenging.

Purpose of the Study:

• To demonstrate on-chip optical trapping of dielectric microbeads and bacteria.
• To utilize one-dimensional optical lattices created by near-field mode beating.
• To enable versatile manipulation of trapped particles in various geometries.

Main Methods:

• Creation of one-dimensional optical lattices via near-field mode beating.
• Utilizing a few-mode silicon nanophotonic waveguide for light guidance.
• Trapping and manipulating dielectric microbeads and bacteria.

Main Results:

• Successful on-chip optical trapping of large numbers of particles.
• Demonstration of periodic trap arrays with various geometries.
• Enabled diverse particle transport and repositioning techniques.

Conclusions:

• Near-field mode-beating optical lattices offer a novel solution for on-chip multi-particle manipulation.
• This technique is readily implementable in lab-on-a-chip devices.
• Potential applications span bio-analysis to nanoparticle processing.