Buffer gas-assisted polarization spectroscopy of 6Li

TL;DR

This paper demonstrates Doppler-free polarization spectroscopy of 6Li atoms enhanced by Ar buffer gas, enabling stable laser locking for laser cooling, with experimental results supported by rate equation calculations.

Contribution

It introduces buffer gas-assisted polarization spectroscopy of 6Li and shows its effectiveness for stable laser frequency locking.

Findings

Buffer gas enhances polarization rotation signals.

Signal dependence on buffer pressure and laser power matches calculations.

Achieved stable laser locking for 6Li cooling.

Abstract

We report on the demonstration of Doppler-free polarization spectroscopy of the D2 line of 6Li atoms. Counterintuitively, the presence of an Ar buffer gas, in a certain pressure range, causes a drastic enhancement of the polarization rotation signal. The observed dependence of the signal amplitude on the Ar buffer pressure and the pump laser power is reproduced by calculations based on simple rate equations. We performed stable laser frequency locking using a dispersion signal obtained by polarization spectroscopy for laser cooling of 6Li atoms.