Low-loss silica-on-silicon waveguides.

Area of Science:

• Integrated photonics
• Materials science

Background:

• Waveguiding structures are essential for integrated photonic circuits.
• Low-loss, wide-wavelength, linear-response devices are highly sought after.

Purpose of the Study:

• To develop and characterize novel low-loss silica waveguides on silicon substrates.
• To investigate the performance of a unique suspended cylinder geometry.

Main Methods:

• Fabrication of silica waveguides with a suspended cylinder design on a silicon substrate.
• Optical characterization of waveguide loss across a broad wavelength range (658-1550 nm).
• Analysis of loss dependence on light polarization and input power.

Main Results:

• Successfully developed and characterized low-loss silica waveguides.
• The suspended cylinder geometry resulted in an air-clad device with high refractive index contrast.
• Measured optical loss remained constant from 658 to 1550 nm.
• Loss was independent of input light polarization and power.

Conclusions:

• The novel suspended cylinder geometry enables effective air cladding, enhancing optical field confinement.
• The developed waveguides exhibit excellent low-loss and broadband performance crucial for integrated photonics.
• These waveguides are suitable for various applications requiring stable optical performance irrespective of polarization or power levels.