High side-mode suppression ratio with a Vernier effect single-mode laser using triple coupled microrings

Area of Science:

• Photonics
• Integrated Optics
• Laser Technology

Background:

• Single-mode lasers with high side-mode suppression ratio (SMSR) are essential for integrated photonics and long-distance communication.
• Achieving high SMSR in lasers remains a significant challenge in optical device development.

Purpose of the Study:

• To demonstrate a novel single-mode laser design with an enhanced SMSR.
• To explore the potential of size-mismatched triple-coupled microrings for laser mode control.

Main Methods:

• Fabrication of a laser device utilizing size-mismatched triple-coupled microrings.
• Precise engineering of structural parameters such as air gap and microring radii to control the free spectral range (FSR).
• Utilizing the Vernier effect for side and higher-order mode suppression.

Main Results:

• Successfully demonstrated a single-mode laser operation with an improved SMSR exceeding 20 dB.
• Achieved stable single-frequency output over a wide range of optical power.
• Experimental results were validated by theoretical calculations and numerical simulations.

Conclusions:

• The developed size-mismatched triple-coupled microring laser offers an effective solution for achieving high SMSR.
• This structural engineering approach opens new avenues for applications in single-mode lasers and high-quality sensors.
• The laser's performance highlights its potential for advanced integrated photonic devices.