Long-range dielectric-loaded surface plasmon-polariton waveguides

Area of Science:

• Photonics and Nanophotonics
• Optical Waveguiding
• Plasmonics

Background:

• Surface plasmon polaritons (SPPs) are electromagnetic waves coupled to the electron oscillations on a metal surface.
• Achieving long propagation distances and tight mode confinement simultaneously in SPP waveguides is crucial for integrated optics.
• Existing SPP waveguide designs often face trade-offs between confinement and propagation length.

Purpose of the Study:

• To propose and analyze a novel long-range dielectric-loaded surface plasmon polariton (LR-DLSPPW) waveguide configuration.
• To achieve simultaneous tight mode confinement and long propagation distances for SPPs at telecom wavelengths.
• To demonstrate the feasibility of this waveguide for integrated photonic applications.

Main Methods:

• Finite-element method (FEM) simulations were employed to analyze the waveguide characteristics.
• The proposed waveguide structure consists of a thin metal stripe sandwiched between dielectric layers and a substrate.
• Optical polymer materials were considered for the dielectric components.

Main Results:

• A specific gold stripe-based LR-DLSPPW configuration was designed and simulated.
• The designed waveguide supports a fundamental LR-DLSPPW mode with a width of 1.6 μm.
• The mode exhibits a propagation length of 3.1 mm at a wavelength of 1.55 μm.

Conclusions:

• The proposed LR-DLSPPW configuration offers a promising solution for achieving both strong mode confinement and long propagation distances.
• The design is compatible with planar fabrication techniques like UV-lithography.
• The structure facilitates integration with electrodes for electro-optic or thermo-optic control, enabling advanced photonic device functionalities.