Research On The Measurement Of The Residence Time And Barrier Height Of Rubidium Atoms On The Surface Of Single Crystal Sapphire

The goal of this thesis is to study the process of collision of rubidium atoms with a sapphire surface and carry out the measurement of the dwell time and heights of a potential barrier for rubidium atoms on the sapphire surface by the Knudsen flow method.Study of the influence of various factors(such as the condition of the sapphire surface)on the dwell time.We have created an experimental setup for measurement and have developed a method for measuring the evolution of the rubidium atoms density by measuring the fluorescence intensity of atoms excited by a probe laser.Besides,we have also proposed recommendations to reduce the effects of optical pumping on the measurement process.We found that the measured dependence of the rubidium atoms dwell time on the sapphire surface on temperature is well described by the Arrhenius formula without diffusion inside of the material.From our study we can make the following conclusions:sapphire is very solid and poros free material and that the collisions and desorbtion of atoms from supfire surface is an example of pure surface phenomenon.