Precise electron beam-based target-wavelength trimming for frequency conversion in integrated photonic resonators

Area of Science:

• Integrated photonics
• Materials science
• Quantum optics

Background:

• Precise wavelength control is vital for integrated photonic devices.
• Current methods often require complex fabrication or lack fine-tuning capabilities.
• Post-fabrication tuning offers a flexible solution for wavelength management.

Purpose of the Study:

• To demonstrate a method for post-fabrication wavelength trimming on a Gallium Phosphide on Silicon Nitride platform.
• To achieve deterministic and individual tuning of multiple devices on a single chip.
• To enable targeted wavelength applications like quantum frequency conversion.

Main Methods:

• Utilizing controlled electron-beam exposure on hydrogen silsesquioxane cladding.
• Establishing a linear relationship between electron-beam dose and resonant wavelength shift.
• Characterizing second harmonic generation in trimmed devices.

Main Results:

• Achieved deterministic wavelength trimming to within 30 pm of the target wavelength.
• Demonstrated successful tuning of multiple devices on the same chip.
• Obtained devices with quality factors around 10⁴ for second harmonic generation.

Conclusions:

• Post-fabrication trimming using electron-beam lithography is a viable technique for integrated photonics.
• This method enables precise wavelength customization for advanced photonic applications.
• The demonstrated approach is essential for applications such as quantum frequency conversion.