Isolation and one-way effects in diffraction on dielectric gratings with plasmonic inserts

Area of Science:

• Optics and Photonics
• Materials Science
• Electromagnetism

Background:

• Dielectric gratings are fundamental optical components.
• Plasmonic materials offer unique light-matter interaction properties.
• Anomalous diffraction phenomena are crucial for advanced optical devices.

Purpose of the Study:

• To investigate anomalous selectivity of diffraction orders in dielectric gratings with planar plasmonic inserts.
• To explore the suppression of formally propagating diffraction orders.
• To analyze the influence of plasmonic layer properties on diffraction behavior.

Main Methods:

• Theoretical analysis of plane wave diffraction.
• Modeling of dielectric gratings with integrated plasmonic layers.
• Investigation of frequency-dependent electromagnetic field distributions.

Main Results:

• Demonstrated wideband suppression of specific diffraction orders, exceeding previous isolation effects.
• Identified the critical role of the plasmonic layer's permittivity (real part between 0 and 1).
• Observed wideband features like one-way transmission and diffraction-free reflection, alongside narrowband effects.

Conclusions:

• The proposed structures exhibit unique wideband and narrowband diffraction selectivity.
• These findings advance technologies utilizing multibeam operation and field transformation.
• The study highlights the potential of plasmonic inserts for precise control of light propagation.