Tunable Wavelength-Multiplexed Dual-Frequency Bound Pulse in a Carbon-Nanotube-Based Fiber Laser

Area of Science:

• Nonlinear Optics
• Fiber Lasers
• Soliton Dynamics

Background:

• Mode-locked fiber lasers are crucial for generating ultrashort pulses.
• Dual-frequency pulses offer unique properties for applications like optical frequency combs.
• Controlling soliton dynamics in fiber lasers remains a challenge.

Purpose of the Study:

• To demonstrate the coexistence of three wavelength-multiplexed bound dual-frequency pulses.
• To investigate the mechanism for tuning between different bound dual-frequency pulse states.
• To explore the potential for optical frequency comb generation.

Main Methods:

• Experimental setup utilizing an all-fiber mode-locked laser.
• Exploitation of polarization-dependent loss and Er-doped fiber gain peaks.
• Single-wall carbon-nanotube for intensity modulation.
• Coupled Ginzburg-Landau equations for theoretical simulation.

Main Results:

• Achieved wavelength-multiplexed dual-frequency pulses at 1531.1 nm and 1556.6 nm.
• Observed evolution of asynchronous pulses into bound states (doublets) around 1530 nm or 1556 nm.
• Demonstrated switching of relative phase and modulation depth using a polarization controller.

Conclusions:

• The proposed fiber laser successfully generates and controls multiple bound dual-frequency pulses.
• The study provides insights into the complex dynamics of multiple solitons.
• This work offers a potential pathway for advanced optical frequency comb generation.