Optical pulling using evanescent mode in sub-wavelength channels.

Area of Science:

• Photonics
• Optical manipulation
• Nanotechnology

Background:

• Optical evanescent waves in total internal reflection are standard for optical manipulation.
• Existing methods rely on intensity gradients for trapping and scattering forces for transport.

Purpose of the Study:

• To propose a novel optical manipulation scheme using attenuated modes in subwavelength optical channels.
• To demonstrate trapping and transportation forces acting along the same direction within a channel.

Main Methods:

• Creation of an attenuated mode in a sub-wavelength photonic crystal waveguide.
• Quantitative measurement of net pushing and pulling forces.
• Investigation of transverse trapping and manipulation along curved trajectories.

Main Results:

• Demonstrated forces capable of overcoming Brownian motion within a critical length.
• Achieved natural subwavelength trapping in the transverse direction due to the channel.
• Showcased manipulation along bend trajectories without self-acceleration beams.

Conclusions:

• The proposed method offers a distinct approach to optical manipulation using subwavelength channels.
• This technique provides flexible and precise control over particle movement.
• The method is extendable to other channels supporting attenuation modes.