Optical trapping based on microring resonators with a transverse slot structure

Area of Science:

• Optics and Photonics
• Nanotechnology
• Biophysics

Background:

• Optical manipulation is crucial in biology, micro/nanorobotics, and physics.
• Transverse slot optical waveguides enhance optical fields for improved trapping.
• Microring resonators concentrate light at resonance for particle manipulation.

Purpose of the Study:

• To investigate the structural impact on nanoparticle capture using a microring resonator.
• To evaluate the enhancement of optical trapping forces by introducing a transverse slot.

Main Methods:

• Integration of a 50 nm transverse slot into a 5 µm microring resonator.
• Simulation and analysis of optical forces on nanoparticles.

Main Results:

• A substantial increase in maximum bound optical power was observed.
• The structure achieved 3988.8 pN/W for a 50 nm nanosphere (refractive index 1.6).
• This represents a 2292x increase over straight waveguides and a 2.266x increase over microring resonators.

Conclusions:

• The proposed transverse slot microring resonator significantly enhances optical trapping capabilities for nanoscale particles.
• This advancement facilitates the development of sophisticated micro/nanomanipulation techniques.
• The findings open new avenues for precise particle control in various scientific domains.