Modeling the Lamb mode-coupling constant of quantum well semiconductor lasers

Area of Science:

• Laser Physics
• Quantum Optics
• Semiconductor Devices

Background:

• Extended cavity lasers with multiple quantum-well active layers are crucial for tunable laser applications.
• Understanding mode coupling is essential for achieving stable dual-mode operation.

Purpose of the Study:

• To theoretically compute the coupling constant (C) between two emission modes in extended cavity lasers.
• To investigate the influence of laser class (A vs. B) on dual-mode stability.
• To explore the impact of mode profiles, carrier diffusion, and temperature inhomogeneity on mode coupling.

Main Methods:

• Utilized an optimized Monte Carlo model based on Markov chains to simulate carrier and photon dynamics.
• The model describes elementary events over time for theoretical computation.
• Extended the model to analyze spatial and thermal effects within the laser cavity.

Main Results:

• Determined that Class A lasers provide better stability for dual-mode operation compared to Class B lasers.
• The coupling constant (C) was found to be independent of the beating frequency.
• Observed the evolution of C with respect to spatial mode splitting in the gain medium.

Conclusions:

• Class A lasers are preferable for achieving stable dual-mode operation in extended cavity lasers.
• The developed theoretical model accurately predicts experimental results for mode coupling.
• Spatial and thermal factors significantly influence mode coupling and laser stability.