Etchless chalcogenide microresonators monolithically coupled to silicon photonic waveguides

Area of Science:

• Photonics
• Materials Science
• Nanotechnology

Background:

• Silicon photonics offers mature fabrication but suffers from high nonlinear losses.
• Chalcogenides provide low nonlinear losses but are challenging to integrate with silicon.
• Hybrid approaches are needed to combine the advantages of both material systems.

Purpose of the Study:

• To demonstrate a novel method for integrating high-Q chalcogenide microring resonators onto silicon photonics platforms.
• To achieve this integration without post-process etching, simplifying the fabrication workflow.
• To enable low-loss, compact nonlinear photonic devices.

Main Methods:

• Utilizing micro-trench filling and a novel thermal dewetting technique to create chalcogenide strip waveguides.
• Integrating chalcogenide microrings directly into silicon photonic circuits via evanescent coupling.
• Leveraging complementary metal-oxide-semiconductor (CMOS)-compatible nanophotonic fabrication processes.

Main Results:

• Demonstrated the first integration of high-Q chalcogenide microring resonators onto silicon photonics without post-process etching.
• Achieved microrings with a quality factor exceeding 6x10^5 near 1550 nm.
• Measured propagation losses below 0.7 dB/cm for the chalcogenide waveguides.

Conclusions:

• The developed hybrid integration scheme is uncomplicated and does not require modification of existing foundry processes.
• This method offers a promising solution for cost-effective, compact nonlinear photonic devices.
• The technology has potential applications in telecommunications, spectroscopy, and other fields requiring nonlinear optical functionalities.