Temperature Dependent Rubidium-Helium Line Shapes and Fine Structure Mixing Rates

Diode Pumped Alkali Lasers (DPALs) are a new type of laser that uses alkali metal vapor as a gain medium and a buffer gas to control the line shape and kinetics. While these systems were first demonstrated in 2003 [48] they have just recently been scaled to the kilowatt power levels in 2012 [18]. To achieve these powers, the design of the gain cell relied on a set of incomplete line shape and kinetic data. The current focus areas of DPAL research are the continued power scaling of the systems and basic science research into the rates involved within the system. The purpose of this research is to determine the physical parameters of various alkalinoble gas interactions with a high degree of accuracy. The physical parameters of interest here include pressure broadening (), pressure shift ( ), asymmetry ( 0), the quenching rates (k20, k10), and spin-orbit (SO) mixing rates (k12, k21). Various measurements of these line shape parameters and the rates associated with these systems have been taken over the years at low temperatures and usually low pressures. Temperatures of the measurements range from 320 K [39] to 394 K [68] with pressures of 300 Torr [68]. Various theories including the semi-classical approach of Anderson Talman [4, 43] and the full quantum mechanical treatment of Baranger [7] can be used to predict line shape parameters provided that the interaction potentials, are well known