Magneto-optical binding in the near field

Area of Science:

• Plasmonics
• Nanophotonics
• Optical Forces

Background:

• Optical binding describes forces between particles induced by light.
• Near-field interactions are crucial for nanoscale phenomena.
• Plasmonic nanoparticles exhibit unique optical properties.

Purpose of the Study:

• To analytically and numerically demonstrate near-field stable optical binding between two identical plasmonic particles.
• To investigate the control of binding distance and stiffness.
• To explore the influence of the magneto-optical effect on binding.

Main Methods:

• Analytical calculations of optical binding forces.
• Numerical simulations of particle interactions.
• Investigation of plasmonic resonance conditions.
• Inclusion of magneto-optical effects.
• Molecular dynamics simulations for validation.

Main Results:

• Formation of a stable near-field optical binding between identical plasmonic particles.
• Equilibrium binding distance controlled by polarization angle and an explicit formula derived.
• Stable binding achieved near dipole plasmonic resonance frequency, dependent on dielectric function.
• Binding stiffness four orders of magnitude larger than far-field binding.
• Transverse binding formed orthogonal to incident beam propagation.
• Control over binding distance using external magnetic fields via magneto-optical effect.

Conclusions:

• Achieved precise control over near-field optical binding forces between plasmonic nanoparticles.
• Demonstrated a method for tunable nanoparticle assembly using light and magnetic fields.
• The findings pave the way for advanced nanoscale manipulation and device fabrication.