研究目的
To describe the development and application of a thulium fiber laser in an atomic helium spectroscopy experiment for quenching meta-stable singlets of helium isotopes, enabling further investigation of the helium fine structure.
研究成果
The thulium fiber laser effectively quenches the singlet states of atomic helium, providing a convenient and reliable solution for optical pumping and spectroscopy applications. The simplified analysis and published cross-sections support feasible laser designs between 1900 and 2100 nm.
研究不足
The coupling loss from the combiner into the active fiber was higher than expected, primarily due to the low index recoat. The index uniformity of the recoated fiber was not as uniform as commercial fiber.
1：Experimental Design and Method Selection:
The laser was designed with a diode module centered at 793 nm, fused to a multi-mode pump combiner to launch pump power into the active fiber. The laser cavity was created using a highly reflective fiber Bragg grating.
2：Sample Selection and Data Sources:
The experiment utilized a thulium doped fiber for the laser and an atomic beam of meta-stable helium created by electron collisions.
3：List of Experimental Equipment and Materials:
Diode module (BWT Beijing), multi-mode pump combiner (ITF Technologies), thulium doped fiber (Nufern), fiber Bragg grating (O/E Land).
4：Experimental Procedures and Operational Workflow:
The laser was tested for output power and slope efficiency. It was then applied to quench singlet states in a helium atomic beam, with the atomic beam collimated to reduce Doppler broadening.
5：Data Analysis Methods:
A simplified analysis was used to estimate the slope efficiency and threshold of the laser, with parameters adjusted to fit measured values.
独家科研数据包，助您复现前沿成果，加速创新突破
获取完整内容
