Broadly tunable laser based on novel metallic resonant leaky-mode diffraction grating.

Area of Science:

• Optics and Photonics
• Laser Technology

Background:

• Fiber lasers offer versatile light sources for various applications.
• Achieving broad wavelength tunability in fiber lasers is crucial for advanced spectroscopy and telecommunications.

Purpose of the Study:

• To develop a broadly tunable fiber laser using a novel diffraction grating.
• To characterize the performance of the laser system, including its tuning range and efficiency.

Main Methods:

• Utilized a new metallic resonant leaky-mode diffraction grating in a Littrow configuration.
• Employed three fiber-pigtailed semiconductor optical amplifiers for laser gain.
• Experimentally measured diffraction efficiency and laser tuning performance.

Main Results:

• Achieved a broad wavelength tunability from 1058 nm to 1640 nm.
• The diffraction grating exhibited over 90% efficiency for TM polarization in the -1st reflected order across a wide spectral range (1417 nm to 1700 nm).
• The laser demonstrated a 331 nm spectral coverage within a 558 nm tuning band without optical adjustments.

Conclusions:

• The developed fiber laser system demonstrates significant broad wavelength tunability.
• The metallic resonant leaky-mode diffraction grating is a key component for achieving wide tuning ranges.
• Further improvements in tuning range are possible with broader amplification bands from semiconductor optical amplifiers.