Low-loss arrayed waveguide grating at 760 nm.

Area of Science:

• Photonics
• Integrated Optics
• Materials Science

Background:

• Arrayed waveguide gratings (AWGs) are crucial for wavelength division multiplexing.
• Operation at shorter wavelengths like 760 nm presents challenges due to increased scattering and phase errors from fabrication imperfections.

Purpose of the Study:

• To demonstrate an arrayed waveguide grating (AWG) operating at 760 nm with minimal insertion loss.
• To address the challenges of interface roughness and waveguide length errors at 760 nm through improved design and fabrication.

Main Methods:

• Utilized silicon nitride core and silicon dioxide clad waveguides on a silicon platform.
• Minimized interfacial scattering, grating side-order excitation, and phase errors during the AWG design and fabrication process.

Main Results:

• Achieved an arrayed waveguide grating (AWG) with an insertion loss below 0.5 dB at 760 nm.
• Demonstrated effective mitigation of scattering and phase errors critical for short-wavelength operation.

Conclusions:

• The developed AWG is suitable for high-performance photonic integrated circuits.
• Compatibility with heterogeneously integrated lasers enables on-chip spectral beam combining.