Achieving sub-pm wavelength regression via minimum-phase in a single-stream photonic IC

Area of Science:

• Photonics and optical engineering
• Spectroscopy and metrology
• Integrated optics and photonic devices

Background:

• Compact spectrometers typically face a trade-off between resolution, size, and signal quality.
• Existing photonic chip designs often require complex architectures or compromise performance.

Purpose of the Study:

• To introduce a chip-scale photonic architecture that overcomes the resolution-size trade-off in spectrometers.
• To enable high-accuracy wavelength metrology using a compact, single-stream device.
• To explore applications in on-chip sensing and computational spectroscopy.

Main Methods:

• Utilizing simple intensity measurements to extract phase information from light waves.
• Developing a generalized minimum phase design with sparse and non-sequential optical delays.
• Implementing a single-input, single-output photonic chip for accurate phase reconstruction.

Main Results:

• Achieved sub-picometer precision in determining the wavelength of unknown lasers.
• Demonstrated a compact, scalable photonic chip architecture.
• Overcame the traditional spectrometer trade-off between resolution and device size/signal quality.

Conclusions:

• The developed chip-scale spectrometer offers a robust and efficient solution for high-accuracy wavelength metrology.
• This novel architecture paves the way for advanced on-chip sensing and computational spectroscopy.
• The single-stream design enhances performance by reducing loss and complexity compared to traditional spectrometers.