Fast Non-destructive temperature measurement of two-electrons atoms in a magneto-optical trap

TL;DR

This paper presents an improved non-destructive spectroscopic method for accurately measuring the temperature of two-electron atoms in a magneto-optical trap, overcoming previous resolution limits and offering an alternative to time-of-flight techniques.

Contribution

It extends a spectroscopic technique to measure atom cloud temperature in MOTs with enhanced accuracy by analyzing excitation spectra and effects of MOT light, including ground state light shift and Rabi broadening.

Findings

Accurate temperature measurement of Ytterbium and alkaline-earth atoms in MOTs.

Successful comparison of measured light shifts and broadening with theoretical calculations.

Demonstration of spectroscopy on free-falling atoms as an alternative temperature measurement method.

Abstract

We extend the technique originally proposed by Honda et al.to measure the temperature of Ytterbium and alkine-earth atoms confined in a Magneto-Optical Trap (MOT). The method is based on the analysis of excitation spectra obtained by probing the 1S0->3P1 inter-combination line. Thanks to a careful analysis and modeling of the effects caused by the MOT light on the probe transition we overcome the resolution and precision limits encountered in previous works. Ground state light shift and Rabi broadening are measured and successfully compared with calculated values. This knowledge allows us to properly extract the Doppler contribution to the linewidth, thus obtaining a reliable measurement of the cloud temperature. We finally show how spectroscopy on free-falling atoms provides an alternative method to determine the sample temperature which resembles the standard time-of-flight technique.