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Roaming pathways and survival probability in real-time collisional dynamics of cold and controlled bialkali molecules

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 نشر من قبل Svetlana Kotochigova
 تاريخ النشر 2021
  مجال البحث فيزياء
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Perfectly controlled molecules are at the forefront of the quest to explore chemical reactivity at ultra low temperatures. Here, we investigate for the first time the formation of the long-lived intermediates in the time-dependent scattering of cold bialkali $^{23}$Na$^{87}$Rb molecules with and without the presence of infrared trapping light. During the nearly 50 nanoseconds mean collision time of the intermediate complex, we observe unconventional roaming when for a few tens of picoseconds either NaRb or Na$_2$ and Rb$_2$ molecules with large relative separation are formed before returning to the four-atom complex. We also determine the likelihood of molecular loss when the trapping laser is present during the collision. We find that at a wavelength of 1064 nm the Na$_2$Rb$_2$ complex is quickly destroyed and thus that the $^{23}$Na$^{87}$Rb molecules are rapidly lost.



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