Fiber Bragg grating-based linear-cavity fiber laser.

Area of Science:

• Optics and Photonics
• Fiber Lasers
• Optical Communications

Background:

• Mode-division multiplexing (MDM) is crucial for increasing fiber-optic communication capacity.
• Simultaneous lasing of multiple spatial modes at a single wavelength is challenging.

Purpose of the Study:

• To propose and experimentally demonstrate a fiber Bragg grating-based linear-cavity fiber laser.
• To enable simultaneous lasing of LP01, LP11, LP21, and LP02 modes at the same wavelength.

Main Methods:

• Utilized a single-mode fiber Bragg grating as a fundamental mode wavelength selector.
• Employed four few-mode fiber Bragg gratings to reflect different spatial modes (LP01, LP11, LP21, LP02) at the same wavelength.
• Configured four sub-linear cavities by strategically placing gratings.

Main Results:

• Successfully demonstrated a fiber laser capable of simultaneous multi-mode lasing at a single wavelength.
• Achieved reflection of LP01, LP11, LP21, and LP02 modes at the identical wavelength using the proposed grating configuration.
• Established four distinct sub-linear cavities within the laser system.

Conclusions:

• The developed fiber laser is significant for advancing mode-division multiplexing fiber-optic communications.
• This technology offers a new pathway for high-capacity optical data transmission.
• The simultaneous multi-mode lasing capability at a single wavelength is a key innovation.