Formation of directed beams from atom lasers

The problem of creating well-collimated beams of atoms escaping from a trap is studied, This problem is of high importance for the realization of atom lasers. Nonadiabatic dynamics of neutral atoms in nonuniform magnetic fiel ds, typical of quadrupole magnetic traps, has been considered. The main res ult of this report is that an unusual semiconfining regime of motion is fou nd, when atoms are confined from one side of an axis but are not confined f rom another side. This regime can be achieved by means of only magnetic fie lds. The formed atomic beam can be forwarded in arbitrary direction.