Ridge waveguide assisted highly efficient transverse-electric-pass polarizer based on a hybrid plasmonic waveguide

Area of Science:

• Photonics
• Nanotechnology
• Materials Science

Background:

• Plasmonic polarizers often suffer from high insertion loss due to metal-optical field interactions.
• Developing compact and efficient polarizers is crucial for integrated optics.

Purpose of the Study:

• To propose an ultra-compact and low-loss transverse-electric (TE)-pass polarizer.
• To reduce insertion loss (IL) and device length in hybrid plasmonic polarizers.

Main Methods:

• Utilizing a hybrid plasmonic ridge waveguide structure on a silicon-on-insulator platform.
• Considering electric field distribution and periodic coupling between transverse magnetic (TM) and plasmonic modes.
• Employing the finite-difference time-domain (FDTD) method for numerical simulations.

Main Results:

• A 4.2 μm-long polarizer demonstrated a high extinction ratio (ER) of ~29.5 dB.
• Achieved a low insertion loss (IL) of 0.18 dB at 1550 nm wavelength.
• Obtained an ER > 23 dB over a 100 nm bandwidth.

Conclusions:

• The proposed hybrid plasmonic waveguide structure effectively minimizes IL and device length.
• This ultra-compact polarizer offers excellent performance across a wide bandwidth, suitable for optical integration.