Magneto-optical trapping of chromium atoms

We have constructed a magneto-optical trap for chromium atoms. Using trapping light at 425 nm and two repumping lasers tuned to intercombination transitions, over 10(6) atoms were trapped and average densities of over 10(16) m(-3) were obtained. Nonexponential loss of atoms is observed at high densities indicating inelastic collisions between trapped atoms. Over a range of trapping conditions, the density-dependent trap loss rate constant beta is extracted from fluorescence decay curves and found to have values in the range of 10(-15) m(3) s(-1) much larger than is observed in alkali-metal traps.