Higher order microfibre modes for dielectric particle trapping and propulsion

Area of Science:

• Photonics and optical engineering
• Microscale physics
• Nanotechnology

Background:

• Optical manipulation near micro- and nanofibres is key for microparticle control and atom trapping.
• Existing research primarily uses the fundamental mode, limiting manipulation capabilities.
• Higher order modes offer extended evanescent fields and larger amplitudes at the fibre waist.

Purpose of the Study:

• To demonstrate a microfiber/optical tweezers system utilizing higher order modes for enhanced particle manipulation.
• To investigate the propulsion speed of dielectric particles using these modes.
• To explore potential applications in atom trapping and quantum technologies.

Main Methods:

• Excitation of the first group of higher order modes at the microfibre waist.
• Utilizing a compact microfiber/optical tweezers system.
• Experimental measurement and theoretical calculation of particle propulsion velocity.

Main Results:

• Demonstrated trapping and propulsion of dielectric particles using higher order modes.
• Observed significant speed enhancement for polystyrene particles (1-5 μm diameter) compared to the fundamental mode.
• Achieved an 8-fold increase in optical propelling velocity for a 3 μm particle at 25 mW waist power.

Conclusions:

• Higher order modes in microfibers significantly enhance optical particle propulsion speeds.
• This method provides a novel approach for microparticle manipulation and trapping.
• Potential applications include trapping laser-cooled atoms for quantum networks and advanced optical manipulation.