Study Of He-Ne Discharge In Hollow Fiber

Hollow-core photonic crystal fiber (HC-PCF) is a popular direction of lasers researchrecently. Compared to traditional fiber lasers, it has potential advantages, such as higheroutput power. As a pre-research work of the HC-PCF helium-neon gas laser, this subject isan essential part.Technical characteristics and application of He-Ne lasers is mentioned in the thesis, andlow power output is a shortage of He-Ne lasers. Combined with the structural characteristicsof HC-PCF, it is possible to improve output power of He-Ne lasers by using HC-PCF asdischarge tube.As common HC-PCF is applied in communication, HC-PCF which can transmit632.8nm wavelength should be specially designed. Photonic band gap characteristics of HC-PCFis introduced in the thesis, and a kind of632.8nm HC-PCF structure is obtained by usingfinite element method to analyze HC-PCF.Hollow fiber instead of HC-PCF is used in experiments as a pre-research. In this thesis,He-Ne DC discharge in Hollow fiber is studied, including the discharge circuit, vacuumsystem, gas chambers and spectral detection system.Theories and methods of spectroscopic diagnostics of discharge plasmas are describedin the thesis, including theories and methods of detecting gas temperature, electron densityand electron temperature. Characteristic of discharge plasmas in our experiments is found atlast.In order to study laser gain of discharge plasmas at the wavelength of632.8nm, aspectrometer and a632.8nm He-Ne laser is used in experiments, and the conclusion is thatthe632.8nm laser is enhanced through plasmas.