Broad-range self-sweeping single-frequency linearly polarized Tm-doped fiber laser

Area of Science:

• Optics and Photonics
• Laser Physics
• Spectroscopy

Background:

• Fiber lasers offer tunable wavelength operation for various applications.
• Precise control over laser output, such as pulse characteristics and frequency stability, is crucial for high-resolution spectroscopy.

Purpose of the Study:

• To experimentally demonstrate a linearly polarized, tunable thulium-doped fiber laser.
• To characterize the laser's ability to generate single longitudinal mode pulses with a sweeping frequency.
• To apply the developed laser source for measuring water absorption spectra.

Main Methods:

• Development of a thulium-doped fiber laser cavity.
• Implementation of a tuning mechanism to achieve a wide wavelength sweeping range.
• Characterization of pulse properties, including pulse duration, polarization, and longitudinal mode content.
• Utilizing the laser's sweeping frequency output for high-resolution absorption spectroscopy of water vapor.

Main Results:

• A linearly polarized thulium-doped fiber laser was successfully demonstrated.
• The laser exhibited a wavelength sweeping range of up to 26 nm around 1.92 μm.
• Periodic microsecond pulses, each containing single longitudinal mode radiation, were generated.
• A highly linear frequency sweep of approximately 8 MHz per pulse was achieved.
• The laser was effectively applied to measure the spectrum of water absorption lines in air.

Conclusions:

• The developed fiber laser provides a stable, tunable, and single-mode output.
• The laser's characteristics are suitable for high-resolution spectroscopic measurements.
• This work demonstrates a valuable tool for atmospheric spectroscopy and related fields.