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arXiv · 1008.5127

Cold heteromolecular dipolar collisions

Brian C. Sawyer·Benjamin K. Stuhl·Mark Yeo·Timur V. Tscherbul·Matthew T. Hummon·Yong Xia·Jacek Klos·David Patterson·John M. Doyle·Jun Ye
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Abstract

We present the first experimental observation of cold collisions between two different species of neutral polar molecules, each prepared in a single internal quantum state. Combining for the first time the techniques of Stark deceleration, magnetic trapping, and cryogenic buffer gas cooling allows the enhancement of molecular interaction time by 10$^5$. This has enabled an absolute measurement of the total trap loss cross sections between OH and ND$_3$ at a mean collision energy of 3.6 cm$^{-1}$ (5 K). Due to the dipolar interaction, the total cross section increases upon application of an external polarizing electric field. Cross sections computed from \emph{ab initio} potential energy surfaces are in excellent agreement with the measured value at zero external electric field. The theory presented here represents the first such analysis of collisions between a $^2Π$ radical and a closed-shell polyatomic molecule.

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Brian C. Sawyer, Benjamin K. Stuhl, Mark Yeo, Timur V. Tscherbul, Matthew T. Hummon, Yong Xia, Jacek Klos, David Patterson, John M. Doyle, Jun Ye. 2010-08-30. Cold heteromolecular dipolar collisions. https://doi.org/10.1039/c1cp21203f

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