Magneto-optical trapping of Yb atoms using an intercombination transition

We report the magneto-optical trapping of ytterbium atoms using the ${6s}^2{}^1{S}_0-6s6p{}^3{P}_1$ intercombination transition. The magneto-optical trap is continuously loaded from an atomic beam decelerated by a Zeeman-tuned atomic-beam slower operated at the ${6s}^2{}^1{S}_0-6s6p{}^1{P}_1$ transition. Among seven stable isotopes of ytterbium, six isotopes $\mathrm{of}{\hspace{0.5em}}^{170}\mathrm{Y}\mathrm{b},$ ${}^{171}\mathrm{Yb},$ ${}^{172}\mathrm{Yb},$ ${}^{173}\mathrm{Yb},$ ${}^{174}\mathrm{Yb},$ and ${}^{176}\mathrm{Yb}$ are successfully trapped. The number and density of the trapped atoms are about ${10}^8$ and ${10}^{11}\hspace{0.5em}{\mathrm{cm}}^{-3},$ respectively. The temperature of atoms is estimated to be about $20\hspace{0.5em}\mu \mathrm{K}$ from the time-of-flight measurement. The decay time of the trapped atoms after stopping the loading of atoms is about 3 s.