Nanoparticle Deep-Subwavelength Dynamics Empowered by Optical Meron-Antimeron Topology

Area of Science:

• Photonics and Nanotechnology
• Topological Optics
• Optical Manipulation

Background:

• Optical merons are nonplanar topological textures typically found in surface plasmon polaritons and photonic crystals' reciprocal space.
• Previous research focused on merons in reciprocal space, limiting their application in real-space phenomena.

Purpose of the Study:

• To report the formation of Poynting-vector merons in the real space of a photonic crystal.
• To explore the potential of these optical merons for subwavelength-resolution nanoparticle manipulation.
• To demonstrate a novel application of topological textures in optical manipulation.

Main Methods:

• Utilized Γ-point illumination in a photonic crystal to generate Poynting-vector merons in real space.
• Investigated the interaction of optical merons with gold nanoparticles (AuNPs) of varying sizes.
• Analyzed radiation pressure and optical gradient forces exerted by merons and antimerons.

Main Results:

• Successfully formed Poynting-vector merons in the real space of a photonic crystal.
• Demonstrated that staggered merons and antimerons induce distinct forces on large and small AuNPs, respectively.
• Achieved simultaneous trapping or opposite-direction orbiting of differently sized AuNPs, mimicking a galaxy system.
• Showcased precise separation of AuNPs (10 nm precision) under flow conditions (>1 mm/s).

Conclusions:

• Optical merons in real space offer a novel mechanism for precise optical manipulation of nanoparticles.
• The study highlights the potential for deep-subwavelength precision and switchable topology in lossless optical environments.
• This work opens new avenues for utilizing topological textures in advanced optical technologies.