Waveguide polarizers with hydrogenated amorphous silicon claddings.

Area of Science:

• Photonics and Waveguide Technology
• Materials Science for Optical Devices
• Integrated Optics

Background:

• Waveguide polarizers are crucial components in photonic integrated circuits for controlling light polarization.
• Existing methods for fabricating waveguide polarizers face challenges in achieving high extinction ratios and precise mode control.
• The development of advanced cladding materials and fabrication techniques is essential for improving polarizer performance.

Purpose of the Study:

• To fabricate and characterize novel TE- and TM-pass waveguide polarizers.
• To investigate the effect of hydrogenated amorphous silicon claddings on waveguide polarizer performance.
• To demonstrate a high-precision measurement technique for waveguide polarizer attenuation.

Main Methods:

• Fabrication of K(+)-Na(+) ion-exchanged channel waveguides in glass.
• Growth of hydrogenated amorphous silicon claddings with precisely tuned thicknesses.
• Characterization of polarization isolation for TE and TM modes.
• Measurement of waveguide polarizer attenuation using photothermal deflection technique.

Main Results:

• Achieved polarization isolation of 42 dB for TE-pass and 35 dB for TM-pass polarizers.
• Demonstrated accurate tuning of cladding thickness for optimal mode coupling.
• Measured waveguide polarizer attenuation as high as 760 dB/cm.

Conclusions:

• Hydrogenated amorphous silicon cladded ion-exchanged waveguides are effective for creating high-performance waveguide polarizers.
• Precise control over cladding thickness is critical for optimizing polarization selectivity.
• The photothermal deflection technique provides a sensitive method for characterizing waveguide polarizer attenuation.