Continuous loading of a magnetic trap

We have realized a scheme for continuous loading of a magnetic trap (MT). ⁵²Cr atoms are continuously captured and cooled in a magneto-optical trap (MOT). Optical pumping to a metastable state decouples atoms from the cooling light. Due to their high magnetic moment (6 μB), low-field seeking metastable atoms are trapped in the magnetic quadrupole field provided by the MOT. Limited by inelastic collisions between atoms in the MOT and in the MT, we load 10⁸ metastable atoms at a rate of 10⁸ atoms/s below 100 μK into the MT. Optical repumping after the loading allows us to realize a MT of ground-state chromium atoms.