# Formation of van der Waals Molecules in Buffer-Gas-Cooled Magnetic Traps

 Title: Formation of van der Waals Molecules in Buffer-Gas-Cooled Magnetic Traps Author: Dalgarno, Alexander; Brahms, Nathan; Tscherbul, Timur; Zhang, Peng; Klos, Jacek; Sadeghpour, Hossein R.; Doyle, John M.; Walker, Thad G. Note: Order does not necessarily reflect citation order of authors. Citation: Brahms, Nathan, Timur V. Tscherbul, Peng Zhang, Jacek Klos, Hossein R. Sadeghpour, Alexander Dalgarno, John M. Doyle, and Thad G. Walker. 2010. Formation of van der Waals molecules in buffer-gas-cooled magnetic traps. Physical Review Letters 105:033001. Full Text & Related Files: Dalgarno_Formation.pdf (231.0Kb; PDF) Abstract: We predict that a large class of helium-containing cold polar molecules form readily in a cryogenic buffer gas, achieving densities as high as 10$$^{12}$$  cm$$^{-3}$$. We explore the spin relaxation of these molecules in buffer-gas-loaded magnetic traps and identify a loss mechanism based on Landau-Zener transitions arising from the anisotropic hyperfine interaction. Our results show that the recently observed strong $$T^{-6}$$ thermal dependence of the spin-change rate of silver (Ag) trapped in dense $$^{3}$$He is accounted for by the formation and spin change of Ag$$^{3}$$He van der Waals molecules, thus providing indirect evidence for molecular formation in a buffer-gas trap. Published Version: doi:10.1103/PhysRevLett.105.033001 Terms of Use: This article is made available under the terms and conditions applicable to Other Posted Material, as set forth at http://nrs.harvard.edu/urn-3:HUL.InstRepos:dash.current.terms-of-use#LAA Citable link to this page: http://nrs.harvard.edu/urn-3:HUL.InstRepos:5125274 Downloads of this work: