Note: Broadly tunable all-fiber ytterbium laser with 0.05 nm spectral width based on multimode interference filter

Area of Science:

• Photonics and Optical Engineering
• Fiber Laser Technology

Background:

• Multimode interference (MMI) filters offer narrow transmission bandwidth and large self-imaging wavelength intervals.
• Fiber lasers are crucial for various applications requiring specific light characteristics.

Purpose of the Study:

• To construct and implement an all-fiber ytterbium-doped fiber laser.
• To achieve broad wavelength tunability and narrow spectral width of the output beam using an MMI filter.

Main Methods:

• An all-fiber ytterbium-doped fiber laser was constructed.
• A multimode interference filter was integrated into the laser cavity.
• An in-fiber polarization controller was used to tune the filter's peak transmission wavelength.

Main Results:

• The implemented MMI filter enabled broad wavelength tunability.
• A tuning range of over 30 nm (1038 nm-1070 nm) was demonstrated.
• The output beam exhibited a narrow spectral width of 0.05 nm.

Conclusions:

• The developed all-fiber laser system successfully integrates an MMI filter for tunable, narrow-linewidth operation.
• The simple tuning mechanism using a polarization controller provides effective control over the laser's output wavelength.
• This technology is promising for applications demanding precise wavelength control in fiber lasers.