A full vectorial mapping of nanophotonic light fields

Area of Science:

• Optics and Photonics
• Nanotechnology
• Electromagnetism

Background:

• Light comprises coupled electric and magnetic fields, with intricate interactions most prominent in nanophotonic near fields.
• Subwavelength-scale field variations in nanophotonics lead to complex phenomena like extraordinary optical momentum and superchiral fields.
• Understanding these phenomena necessitates nanoscale measurements of the complete optical field vector.

Purpose of the Study:

• To introduce a robust algorithm for disentangling all six electric and magnetic field components from a single near-field measurement.
• To enable nanoscale measurements of the complete optical field vector without requiring a priori knowledge of the sample or numerical modeling.

Main Methods:

• Development of a novel algorithm to analyze near-field scanning optical microscopy data.
• Application of the algorithm to single near-field measurements.
• Validation using two prototypical nanophotonic structures: a photonic crystal waveguide and a plasmonic nanowire.

Main Results:

• Successfully disentangled all six electric and magnetic field components from single near-field measurements for both structures.
• Demonstrated the algorithm's capability without relying on numerical modeling or prior sample information.
• Provided detailed insights into the complex optical fields of the photonic crystal waveguide and plasmonic nanowire.

Conclusions:

• The developed algorithm offers a robust method for complete optical field vector characterization at the nanoscale.
• This technique facilitates new avenues for studying complex photonic phenomena and designing advanced nanophotonic structures.
• Enables precise understanding and optimization of optical behavior in nanophotonic devices.