Electromagnetically induced transparency in hybrid plasmonic-dielectric system.

Area of Science:

• Plasmonics and Nanophotonics
• Optical Metamaterials
• Solid State Physics

Background:

• Electromagnetically-induced transparency (EIT) is a quantum interference effect.
• Plasmonic-dielectric hybrid systems offer unique light-matter interaction properties.
• Slow light phenomena are crucial for optical signal processing and data storage.

Purpose of the Study:

• To investigate symmetric and asymmetric coupling in a plasmonic-dielectric hybrid system.
• To analyze the induced electromagnetically-induced transparency (EIT) and slow light effects.
• To explore potential applications in plasmonic sensing, all-optical switching, and slow light devices.

Main Methods:

• Theoretical analysis of a hybrid system comprising silver cut-wire pairs and a silicon grating waveguide.
• Numerical simulations to study coupling mechanisms and transmission spectra.
• Analysis of phase dispersion and group index for slow light characterization.

Main Results:

• Both symmetric and asymmetric couplings induce EIT-analogous phenomena.
• Symmetric coupling results in a single transparency window and moderate slow light.
• Asymmetric coupling leads to a double EIT effect, an asymmetrically coupled resonance (ACR), and a significant enhancement of the group index (from <40 to >2500) with high transparency efficiency.

Conclusions:

• The proposed plasmonic-dielectric hybrid system effectively utilizes EIT and ACR for enhanced slow light.
• Asymmetric coupling is a key factor in achieving superior performance compared to symmetric coupling.
• This system serves as a promising building block for advanced plasmonic sensors, all-optical switches, and slow light applications.