• DOI:10.1103/PhysRevA.85.043414
• Corpus ID: 85548812

Formation of deeply bound ultracold Sr 2 molecules by photoassociation near the 1 S + 3 P 1 intercombination line

@article{Skomorowski2012FormationOD,
  title={Formation of deeply bound ultracold Sr 2 molecules by photoassociation near the 1 S + 3 P 1 intercombination line},
  author={Wojciech Skomorowski and Robert Moszynski and Christiane P. Koch},
  journal={Physical Review A},
  year={2012},
  volume={85},
  pages={043414}
}

• W. Skomorowski, R. Moszynski, C. Koch
• Published 20 March 2012
• Physics
• Physical Review A

We predict feasibility of the photoassociative formation of Sr${}_{2}$ molecules in arbitrary vibrational levels of the electronic ground state based on state-of-the-art ab initio calculations. Key is the strong spin-orbit interaction between the $c\phantom{\rule{0.16em}{0ex}}$${}^{3}\phantom{\rule{-0.16em}{0ex}}{\ensuremath{\Pi}}_{u}$, $A\phantom{\rule{0.16em}{0ex}}$${}^{1}\phantom{\rule{-0.16em}{0ex}}{\ensuremath{\Sigma}}_{u}^{+}$, and $B\phantom{\rule{0.16em}{0ex}}$${}^{1}\phantom{\rule{-0.16em}{0ex}}{\ensuremath{\Sigma}}_{u}^{+}$ states. It creates not only an effective dipole moment allowing free-to-bound transitions near the ${}^{1}\phantom{\rule{-0.16em}{0ex}}S+{}^{3}\phantom{\rule{-0.16em}{0ex}}{P}_{1}$ intercombination line but also facilitates bound-to-bound transitions via resonantly coupled excited-state levels to deeply bound levels of the ground $X\phantom{\rule{0.16em}{0ex}}$${}^{1}\phantom{\rule{-0.16em}{0ex}}{\ensuremath{\Sigma}}_{g}^{+}$ potential, with ${v}^{\ensuremath{'}\ensuremath{'}}$ as low as ${v}^{\ensuremath{'}\ensuremath{'}}=6$. The spin-orbit interaction is responsible for both optical pathways. Therefore, those excited-state levels that have the largest bound-to-bound transition moments to deeply bound ground-state levels also exhibit a sufficient photoassociation probability, comparable to that of the lowest weakly bound excited-state level previously observed by Zelevinsky et al. [Phys. Rev. Lett. 96, 203201 (2006)]. Our study paves the way for an efficient photoassociative production of Sr${}_{2}$ molecules in ground-state levels suitable for experiments testing the electron-to-proton mass ratio.