Dual-parameter chiral detection at the single-particle level enabled by surface cosine waves

Area of Science:

• Nanophotonics
• Chiroptical Spectroscopy
• Quantum Optics

Background:

• Accurate single-particle chirality probing is crucial for chiral molecular sensing and enantioselective nanophotonic technologies.
• Conventional methods average measurements, masking individual particle variations.
• Existing single-particle techniques lack phase information, limiting chiral characterization.

Purpose of the Study:

• To introduce a dual-parameter chiral sensing platform for simultaneous amplitude and phase asymmetry detection at the single-particle level.
• To overcome the limitations of intensity-only measurements in current chiroptical techniques.
• To enable comprehensive electromagnetic characterization of single-particle chirality.

Main Methods:

• Development of a surface cosine waves (SCWs) based chiral sensing platform.
• SCWs generate a polarization-balanced interferometric field with specific phase offsets.
• Simultaneous measurement of circular scattering dichroism (CSD) and circular scattering retardance (CSR) upon interaction with chiral scatterers.

Main Results:

• The SCW platform successfully captures both amplitude and phase asymmetries of single chiral particles.
• The dual metrics (CSD and CSR) provide a comprehensive characterization of chirality.
• Demonstrated high-sensitivity, single-particle chiral sensing capabilities.

Conclusions:

• The presented dual-parameter platform offers a robust and generalizable approach for single-particle chiral sensing.
• This method advances chiroptical metrology by incorporating phase information.
• Paves the way for next-generation nanophotonic devices and chiral analysis.