Spin-orbit interaction-mediated measurement of surface chirality

Area of Science:

• Optics and Photonics
• Condensed Matter Physics
• Materials Science

Background:

• Spin-orbit interaction in light beams leads to spatially non-uniform polarization.
• This effect arises from the superposition of orthogonal field components and polarization-dependent interface reflections.

Purpose of the Study:

• To investigate the transformation of optical vortices induced by spin-orbit interaction.
• To utilize this transformation for quantifying the chiral parameter of materials.

Main Methods:

• Focused-reflected light beam experiments.
• Polarization filtering of the output beam.
• Jones matrix-based simulations.
• Experimental measurement of vortex trajectories.

Main Results:

• An interchangeable transformation of l=∓2 charge vortex into two (∓) unit charge vortices was observed for σ=±1 circular polarization.
• The transformation follows a predictable optical vortex trajectory dependent on input beam polarization and surface characteristics.
• The vortex trajectory was successfully used to quantify the sign and magnitude of a quartz crystal's chiral parameter.

Conclusions:

• The spin-orbit interaction provides a novel method for optical vortex manipulation.
• Optical vortex trajectory analysis is a viable technique for characterizing material chirality.
• Experimental results align with theoretical predictions from Jones matrix simulations.