An on-chip hybrid plasmonic light steering concentrator with ∼96% coupling efficiency

Area of Science:

• Photonics
• Plasmonics
• Nanotechnology

Background:

• Integrated optics relies on efficient light manipulation.
• Plasmonic devices offer subwavelength light confinement.
• Silicon-on-insulator (SOI) waveguides are standard in photonic integrated circuits.

Purpose of the Study:

• To propose and theoretically investigate a novel plasmonic light steering concentrator (PLSC).
• To demonstrate efficient light coupling and focusing using a hybrid photonic-plasmonic structure.
• To achieve high field enhancement at the nanoscale.

Main Methods:

• Theoretical study of a hybrid photonic-plasmonic sandwich structure.
• Coupled-mode theory to analyze the coupling mechanism between waveguide mode and plasmonic modes.
• Numerical simulations to obtain coupling efficiency and field confinement.

Main Results:

• Achieved over 96% coupling efficiency at 1500 nm telecommunication wavelength.
• Demonstrated light steering to a perpendicular metal taper with a 15 nm apex radius.
• Obtained a lateral mode width of approximately 110 nm at the apex.
• Calculated field enhancement exceeding 10^7 compared to the silicon waveguide.

Conclusions:

• The proposed PLSC effectively steers and focuses light with high efficiency.
• The hybrid structure enables significant field enhancement for nanoscale applications.
• This device holds potential for advanced photonic integrated circuits and sensing applications.