Optical feedback induced oscillation bursts in two-state quantum-dot lasers.

Area of Science:

• Quantum optics
• Semiconductor lasers
• Nonlinear dynamics

Background:

• Quantum dot lasers offer unique properties due to their discrete energy levels.
• Optical feedback is a critical parameter influencing laser dynamics and stability.
• Understanding complex dynamics in lasers is crucial for advanced applications.

Purpose of the Study:

• To investigate the effect of short optical feedback on a two-state quantum dot laser.
• To identify parameter regions leading to distinct oscillation behaviors.
• To analyze the underlying mechanisms of observed dynamics.

Main Methods:

• Experimental investigation of a two-state quantum dot laser under varying optical feedback.
• Bifurcation analysis to understand the transition to different dynamic regimes.
• Comparison with dynamics observed in single-color semiconductor lasers.

Main Results:

• Identified a parameter space for two-color anti-phase oscillation bursts, where ground and excited states alternate emission.
• Demonstrated that these bursts originate from a torus-bifurcation of a two-state periodic orbit.
• Observed a cascade of period-doubling bifurcations leading to chaotic dynamics in the burst envelope.

Conclusions:

• Quantum dot lasers with optical feedback exhibit rich and complex dynamics.
• The interaction between electronic and photonic timescales drives these intricate behaviors.
• Findings provide insights into controlling and utilizing complex dynamics in quantum dot lasers.