Buffer gas cooling and trapping of atoms with small effective magnetic moments

¹ Harvard/MIT Center for Ultracold Atoms - Cambridge, MA 02138, USA
² Department of Physics, Harvard University - Cambridge, MA 02138, USA
³ Department of Physics, MIT - Cambridge, MA 02139, USA

Received: 5 April 2004
Accepted: 10 May 2004

Abstract

We have extended buffer gas cooling to trap atoms with small effective magnetic moments . For , 10¹² atoms were buffer gas cooled, trapped, and thermally isolated in ultra high vacuum with roughly unit efficiency. For , the fraction of atoms remaining after full thermal isolation was limited by two processes: wind from the rapid removal of the buffer gas and desorbing helium films. In our current apparatus we trap atoms with , and thermally isolate atoms with . This triples the number of atomic species which can be buffer gas cooled and trapped in thermal isolation. Extrapolation of our results and simulations of the loss processes indicate that it is possible to trap and evaporatively cool atoms using buffer gas cooling.