Saturated absorption spectroscopy of helium 2S-3P transition

  • 陳 建佑

Student thesis: Master's Thesis


The structure of helium atoms is simple and stable so that helium atoms are regarded as the fundamental particles in the field of many-body problems Helium spectrum play an important role on theoretical examination and physical model checking On the other hand helium can be easily found in outer space the spectrum of helium are widely used in the field of astrophysics Doppler broadening is an important problem in the field of high precision measurement There exists many kinds of methods to overcome this problem of Doppler broadening such as saturation absorption spectrum two photon transition spectrum and electromagnetically induced transparency spectrum and so on The research purpose of this thesis is to observe the Doppler-free spectrum of helium 2S-3P transitions For this reason we construct an optical system that include laser source frequency doubling system helium discharge system Fabry-Perot cavity and saturated absorption spectroscopy We observed both absorption and saturated absorption signals using our optical system The saturated absorption signals we have observed were J=0、J=1 and J=2 dips and other three dip of crossover We check the linewidth frequency distance of these signal and fitting these signals to make sure that the dips we observed are the helium 2S-3P transitions Some related parameters pressure shift light shift and discharge power-dependent experiments are also analyzed in this thesis These parameter-dependent experiments can help us optimize signals enhance S/N ratio
Date of Award2014 Aug 1
Original languageEnglish
SupervisorHsiang-Chen Chui (Supervisor)

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