Spectrometer based on a compact disordered multi-mode interferometer

Area of Science:

• Photonics and optical engineering
• Integrated optics
• Spectroscopy

Background:

• Photonic integrated circuits (PICs) offer miniaturization and scalability for optical systems.
• Spectrometers are crucial for wavelength analysis across scientific and industrial fields.
• Silicon-on-insulator (SOI) technology enables advanced photonic device fabrication.

Purpose of the Study:

• To present a compact, CMOS-compatible photonic integrated circuit (PIC) based spectrometer.
• To demonstrate a novel spectrometer design integrating a dispersive array element with a multimode interferometer (MMI).
• To characterize the performance of the fabricated spectrometer at the 1310 nm wavelength.

Main Methods:

• Fabrication of a spectrometer on the silicon-on-insulator (SOI) platform.
• Integration of a dispersive array element comprising SiO2-filled scattering holes within an MMI.
• Characterization of the spectrometer's bandwidth and resolution around 1310 nm.

Main Results:

• The developed spectrometer is compact and CMOS compatible.
• The device integrates a dispersive array of SiO2-filled scattering holes within an MMI.
• The spectrometer exhibits a 67 nm bandwidth, a 1 nm lower bandwidth limit, and a 3 nm peak-to-peak resolution at 1310 nm.

Conclusions:

• The presented PIC-based spectrometer offers a promising solution for miniaturized and integrated spectroscopic analysis.
• The novel design combining scattering holes and MMI achieves competitive resolution and bandwidth.
• The CMOS compatibility facilitates potential integration into larger electronic-photonic systems.