Two-dimensional point spread matrix of layered metal-dielectric imaging elements.

Area of Science:

• Optics and Photonics
• Nanotechnology
• Materials Science

Background:

• Two-dimensional (2D) imaging through multilayer structures, particularly metallic flat lenses, is crucial for advanced optical applications.
• The preservation of light polarization states during imaging is a key factor influencing image quality and resolution.
• Understanding polarization effects is essential for designing high-performance optical elements.

Purpose of the Study:

• To investigate the changes in the spatial distribution of light polarization during 2D imaging through multilayer metallic flat lenses.
• To analyze the impact of polarization-dependent amplitude transfer functions on imaging fidelity.
• To explore the application of matrix-form point spread functions (PSFs) for characterizing superlens resolution and designing novel optical elements.

Main Methods:

• Analysis of polarization-dependent amplitude transfer functions for TM (transverse magnetic) and TE (transverse electric) polarizations.
• Development and application of a matrix-form transfer function and point spread function (PSF) to describe 2D imaging.
• Characterization of cross-polarization coupling for spatially modulated beams with linear or circular incident polarization.
• Design and simulation of a diffractive nanoelement using the 2D PSF.

Main Results:

• Incident linear or circular polarization states are not preserved during imaging through the metallic flat lens.
• The difference in amplitude transfer functions for TM and TE polarizations leads to polarization state changes.
• Matrix-form PSFs reveal cross-polarization coupling and are used to assess superlens resolution for various polarization states.
• A novel diffractive nanoelement with two radial slits was designed, demonstrating separation of nondiffracting radial beams and backward power flow.

Conclusions:

• Metallic flat lenses alter the spatial distribution of light polarization during 2D imaging.
• The matrix-form PSF provides a comprehensive tool for analyzing imaging resolution and polarization effects in multilayer systems.
• The demonstrated diffractive nanoelement design highlights the practical application of these findings in manipulating light at the nanoscale.