Magnetic trapping of silver and copper, and anomolous spin relaxation in the Ag-He system
Abstract
We have trapped large numbers of copper and silver atoms using buffer gas cooling. Up to 3x1012 copper atoms and 4x1013 silver 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 >~ 106, suggesting copper and silver are favorable for use in ultracold applications. The temperature dependence of the silver-helium-3 collision rate varies as T5.8. We find that this temperature dependence is inconsistent with the behavior predicted for relaxation arising from the spin-rotation interaction, and conclude that the silver-helium-3 system displays anomalous collisional behavior in the multiple-partial wave regime. Lifetimes of laser ablated gold in helium-3 buffer gas are too short to permit trapping.