Isotopic difference in the heteronuclear loss rate in a two-species surface trap

Abstract

We have realized a two-species mirror-magneto-optical trap containing a mixture of ${}^{87}$Rb (${}^{85}$Rb) and ${}^{133}$Cs atoms. Using this trap, we have measured the heteronuclear collisional loss rate ${\beta }_{Rb-Cs}^{\prime }$ due to intra-species cold collisions. We find a distinct difference in the magnitude and intensity dependence of ${\beta }_{Rb-Cs}^{\prime }$ for the two isotopes ${}^{87}$Rb and ${}^{85}$Rb which we attribute to the different ground-state hyperfine splitting energies of the two isotopes.

4 pages, 2 figures