Cascaded optically injection-locked semiconductor laser, rate equations analysis, frequency response, and its...

Area of Science:

• Optoelectronics
• Semiconductor Lasers
• Optical Communications

Background:

• Optically injection-locked (OIL) semiconductor lasers are crucial for optical communications.
• Existing OIL systems face limitations in phase modulation range and bandwidth.

Purpose of the Study:

• Introduce a novel cascaded OIL semiconductor laser concept.
• Develop new rate equations and mathematical models for the cascaded OIL system.
• Investigate methods to improve phase modulation range and bandwidth.

Main Methods:

• Developed novel rate equations for cascaded OIL semiconductor lasers.
• Derived the locking range and transfer function for frequency response analysis.
• Performed simulations with identical and varied linewidth enhancement factors (α) in slave lasers.
• Proposed temperature variations for managing α values in slave lasers.

Main Results:

• Achieved significant bandwidth broadening near 700 GHz with a strong injection ratio (15 dB) and high bias current.
• Maintained fair gain up to 180 GHz.
• Boosted complex optical signal generation for high-quality complex modulation.
• Demonstrated a novel method for generating varied α values using temperature control.

Conclusions:

• The proposed adjustments in cascaded OIL systems significantly enhance bandwidth and phase modulation capabilities.
• The system is suitable for high-quality complex modulation applications.
• Temperature-controlled variations offer a novel approach to manage α values in slave lasers.