Light induced atomic desorption influence on the spectra of alkali atoms
Стоян Цветков, S. Tsvetkov
Abstract
This work is devoted to a systematic study of the effect of Light-Induced Atomic Desorption (LIAD). LIAD is a non-heating process in which atoms adsorbed on a surface are desorbed by illumination with non-resonant light. The aim of the dissertation is an experimental study of the LIAD process, its influence on the spectra of alkali atoms in optical cells without and with Anti-Relaxation Coating (ARC) and the possibilities of LIAD for optical characterization of ARC, as well as in high resolution spectroscopy. For the first time, the LIAD process under homogeneous illumination was investigated experimentally, whereby the efficiency of the LIAD was significantly increased even for a cell without ARC, the dynamic characteristics are obtained with a better signal to noise ratio and repeatability, and the desorption and adsorption processes are faster. LIAD effect in cells with different ARC coatings has shown that each coating has different desorption and adsorption rates and the results obtained show the possibility of applying the method for optical characterization of ARC. An experimental study of the number of collisions without atomic spin depolarization in cells with different ARCs and the impact of LIAD was performed, as well as various parameters such as laser intensity and cell temperature were investigated.