Efficient Raman Lasing and Raman-Kerr Interaction in an Integrated Silicon Carbide Platform

Area of Science:

• Photonics
• Materials Science
• Quantum Optics

Background:

• Stimulated Raman scattering (SRS) in microresonators is a pathway to Raman lasing.
• Integrated photonic platforms offer miniaturization and enhanced light-matter interaction.

Purpose of the Study:

• To demonstrate an efficient Raman laser using silicon carbide (SiC) microresonators.
• To explore broadband spectral generation via SRS and Kerr microcombs in SiC.

Main Methods:

• Fabrication of silicon carbide microresonators with tailored free spectral range (FSR).
• Precise alignment of Stokes resonance to the Raman gain spectrum center.
• Characterization of Raman gain, power efficiency, and spectral broadening mechanisms.

Main Results:

• Achieved >50% power efficiency in an integrated SiC Raman laser.
• Demonstrated low power threshold (2.5 mW) due to optimized FSR and Stokes resonance.
• Observed cascaded Raman lasing and multiple Raman shifts (777, 204, 266 cm⁻¹).
• Generated Kerr microcombs and broadened spectra using SRS, spanning 1200-1900 nm.

Conclusions:

• Silicon carbide is a promising material for efficient integrated Raman lasers.
• Optimized microresonator design enables low-threshold Raman lasing and broadband spectral generation.
• SRS in SiC microresonators can be combined with Kerr effects for advanced photonic applications.