Self-consistent analysis of photonic-crystal surface-emitting lasers under continuous-wave operation

Area of Science:

• Photonics
• Semiconductor Lasers
• Theoretical Physics

Background:

• Photonic-crystal surface-emitting lasers (PCSELs) are crucial for various optical applications.
• Continuous-wave (CW) operation of PCSELs is often limited by thermal effects.
• Understanding the interplay between thermal management and lasing characteristics is essential for device optimization.

Purpose of the Study:

• To develop a self-consistent theoretical model for simulating PCSELs under CW operation, incorporating thermal effects.
• To analyze how temperature distribution influences optical gain, refractive index, and oscillation modes.
• To investigate methods for achieving high-quality single-mode lasing at high current injection levels.

Main Methods:

• Developed a self-consistent theoretical model for PCSELs.
• Integrated thermal effects arising from current injection into the simulation.
• Solved for coupled changes in optical gain, refractive index, and oscillation modes.
• Analyzed the impact of spatial band-edge frequency distribution on lasing properties.

Main Results:

• The model reveals that thermal effects significantly alter the in-plane optical gain and refractive index distribution.
• Lasing band-edge selectivity and beam quality are directly affected by the temperature-dependent spatial distribution of the photonic crystal's band-edge frequency.
• Single-mode lasing with narrow beam divergence was demonstrated to be achievable even under high CW current injection.

Conclusions:

• Thermal effects are critical for accurate simulation of PCSELs under CW operation.
• Engineering the photonic crystal structure, specifically the lattice constant distribution, can compensate for thermal-induced frequency variations.
• This approach enables the design of high-performance PCSELs with improved beam quality and single-mode operation.