Design of waveguide-integrated semiconductor laser sources for optical frequency comb generation

Area of Science:

• Photonics and Optics
• Semiconductor Devices
• Laser Physics

Background:

• Integrated semiconductor lasers are crucial for optical frequency comb generation.
• Modal dispersion and threshold gain are key parameters affecting comb performance.
• Bragg gratings offer a method for controlling laser cavity properties.

Purpose of the Study:

• To numerically study threshold gain and modal dispersion in integrated semiconductor laser optical frequency comb sources.
• To explore the impact of replacing a cleaved facet with a Bragg grating on mode selection.
• To demonstrate an intracavity method for limiting grating-induced dispersion.

Main Methods:

• Numerical simulation of laser device performance.
• Analysis of threshold gain and modal dispersion.
• Design and simulation of a Bragg grating section integrated into the laser facet.
• Investigation of grating profile modifications for dispersion control.

Main Results:

• Up to 16 modes can be selected at the first harmonic of the Fabry-Perot cavity using the Bragg grating approach.
• The proposed intracavity method effectively limits grating-induced dispersion.
• The grating profile can be directly engineered to manage dispersion.

Conclusions:

• Replacing a cleaved facet with a Bragg grating is a viable strategy for mode selection in semiconductor laser optical frequency combs.
• Intracavity dispersion management through grating profile engineering is demonstrated.
• This approach offers enhanced control over optical frequency comb characteristics.