Enhanced photonic spin Hall shift and scattering efficiency through chiral nanoparticles

Area of Science:

• Optics and Photonics
• Condensed Matter Physics
• Nanotechnology

Background:

• The photonic spin Hall effect (PSHS) arises from light's spin-orbit interaction, but its practical applications are limited by weak interaction strength and low scattering intensity.
• Existing methods struggle to enhance PSHS and scattering in higher-dimensional systems due to these limitations.

Purpose of the Study:

• To investigate how particle chirality influences far-field PSHS and scattering intensity.
• To explore methods for amplifying spin-orbit interaction and optimizing optical properties using chiral particles.

Main Methods:

• Theoretical exploration of the effect of particle chirality on PSHS and scattering.
• Analysis of quasi-dual symmetry and dual transformation in chiral particle systems.
• Investigating near-field optical singularities and their role in spin-orbit interaction.

Main Results:

• Chiral particles exhibit quasi-dual symmetry when incident wave handedness matches particle chirality, amplifying spin-orbit interaction.
• This amplification leads to an enhanced PSHS with a characteristic redshift and optimized far-field scattering intensity.
• Near-field optical singularities induce strong spin-orbit interaction, creating a large effective transverse force.

Conclusions:

• Particle chirality offers a tunable pathway to enhance PSHS and scattering efficiency.
• The findings provide a method to optimize optical properties without altering particle geometry.
• This approach may enable the characterization of nanoparticle handedness.