Proposal for a hybrid 2D MOT/molasses configuration for potassium-41

We report a proposed design for a compact 2D MOT-optical molasses hybrid for potassium-41 atoms. Adding electromagnets to a previously-reported permanent-magnet based 2D MOT [G. Lamporesi et al$.$, Rev. Sci. Instrum. 84, 063102 (2013)], we show it is possible to flatten the magnetic field at the trap's center, creating a region suitable for molasses. The remaining magnetic field at the fringes of the molasses provides a restoring force sufficient to keep the atoms trapped. This technique should reduce the rate of atom escape from the molasses and allow cooling times substantially longer than in a standard, un-trapped molasses.