Three-dimensional graphene based passively mode-locked fiber laser.

Area of Science:

• Optics and Photonics
• Materials Science
• Nanotechnology

Background:

• Saturable absorbers (SAs) are crucial for generating ultrashort pulses in mode-locked lasers.
• Graphene, with its unique optical properties, has shown promise as an SA material.
• Developing cost-effective and high-performance SAs remains an active area of research.

Purpose of the Study:

• To develop and demonstrate a novel all-fiber passively mode-locked fiber laser.
• To investigate the efficacy of three-dimensional (3D) graphene as a saturable absorber (SA) in such lasers.
• To explore a simple fabrication method for 3D graphene-based SAs.

Main Methods:

• Synthesized 3D graphene using template-directed chemical vapor deposition (CVD).
• Fabricated a saturable absorber by sandwiching freestanding 3D graphene between fiber connectors.
• Constructed an all-fiber passively mode-locked fiber laser incorporating the 3D graphene SA.

Main Results:

• The 3D graphene-based SA successfully generated high-quality mode-locked pulses.
• Stable output pulses with a ~9.9 MHz repetition rate and ~1 ps pulse width were achieved.
• The laser system delivered an average output power of ~10.5 mW in the single pulse region.

Conclusions:

• Freestanding 3D graphene is an effective saturable absorption material for passively mode-locked lasers.
• The developed fabrication method offers a simple and efficient way to create graphene-based SAs.
• This work paves the way for advanced fiber laser systems utilizing 3D graphene.