Franck-Condon Factors and Radiative Lifetime of the A^{2}\Pi_{1/2} - X^{2}\Sigma^{+} Transition of Ytterbium Monoflouride, YbF

TL;DR

This study measures the Franck-Condon factors and radiative lifetime of YbF's electronic transition, providing data crucial for laser cooling applications and comparing experimental results with theoretical predictions.

Contribution

The paper provides the first experimental determination of Franck-Condon factors and the radiative lifetime of YbF's A^{2}\Pi_{1/2} state, validating theoretical models.

Findings

Radiative lifetime of 28±2 ns for the A^{2}\Pi_{1/2} state

Transition dipole moment of 4.39±0.16 D

Measured Franck-Condon factors agree with RKR predictions

Abstract

The fluorescence spectrum resulting from laser excitation of the A^{2}\Pi_{1/2} - X^{2}\Sigma^{+} (0,0) band of ytterbium monofluoride, YbF, has been recorded and analyzed to determine the Franck-Condon factors. The measured values are compared with those predicted from Rydberg-Klein-Rees (RKR) potential energy curves. From the fluorescence decay curve the radiative lifetime of the A^{2}\Pi_{1/2} state is measured to be 28\pm2 ns, and the corresponding transition dipole moment is 4.39\pm0.16 D. The implications for laser cooling YbF are discussed.