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arXiv:0804.0766 · Physical Review Letters

Magnetic Trapping of Silver and Copper, and Anomalous Spin Relaxation in the Ag-He System

Nathan Brahms, Bonna K. Newman, Cort Johnson, Thomas J. Greytak, Daniel Kleppner, John M. Doyle

Published Sep 4, 2008• 36 citations
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Abstract

We have trapped large numbers of copper (Cu) and silver (Ag) atoms using buffer-gas cooling. Up to $3\ifmmode\times\else\texttimes\fi{}{10}^{12}\text{ }\text{ }\mathrm{Cu}$ atoms and $4\ifmmode\times\else\texttimes\fi{}{10}^{13}\text{ }\text{ }\mathrm{Ag}$ atoms are trapped. Lifetimes are as long as 5 s, limited by collisions with the buffer gas. Ratios of elastic to inelastic collision rates with He are $\ensuremath{\gtrsim}{10}^{6}$, suggesting Cu and Ag are favorable for use in ultracold applications. The temperature dependence of the $\mathrm{Ag}\mathrm{\text{\ensuremath{-}}}^{3}\mathrm{He}$ collision rate varies as ${T}^{5.8\ifmmode\pm\else\textpm\fi{}0.4}$. We find that this temperature dependence is inconsistent with the behavior predicted for relaxation arising from the spin-rotation interaction, and conclude that the $\mathrm{Ag}\mathrm{\text{\ensuremath{-}}}^{3}\mathrm{He}$ system displays anomalous collisional behavior in the multiple-partial wave regime. Gold (Au) was ablated into $^{3}\mathrm{He}$ buffer gas, however, atomic Au lifetimes were observed to be too short to permit trapping.

DOI
10.1103/physrevlett.101.103002

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