Study of Rb - vapor coated cell; atomic diffusion and cell curing process

TL;DR

This study investigates the diffusion and curing processes of Rb vapor in a coated cell, revealing how polymerization affects atom behavior and providing a method to determine diffusion coefficients from cell parameters.

Contribution

It introduces a way to accurately determine atomic diffusion coefficients in coated cells and explains the curing process through polymerization effects.

Findings

Diffusion coefficient depends on cell curing time.

Curing process explained by polymerization of coating.

Long dwell times of Rb atoms on PDMS discussed.

Abstract

We present the results of the study of an optical resonant cell filled by a vapor of the Rb atoms and coated with a non-stick polydimethylsiloxane (PDMS) polymer. We show that it is possible to define correctly the diffusion coefficient of the atoms in the coating, using geometric parameters of the cell and the vapor density in the cell volume only. The dependence of the diffusion coefficient on the cell curing time is presented. It is shown that the mysterious cell curing process can be explained in terms of the polymerization of the polymer coating by alkali atoms. Anomalous long dwell time of the Rb atoms on the PDMS coating is discussed as well.