Atomic motion in hollow submicron circular cylinders - art. no. 033401

The motion of atoms inside a long hollow cylindrical waveguide with a circu lar cross section is investigated, The guide is assumed to have subwaveleng th dimensions, in which case the spontaneous decay process is effected only by emission of a few possible cavity modes. The characteristics of the ato mic motion in the guide are explored in the presence of an excited waveguid e mode. We show that the atomic motion in this case is determined by an axi al channelling force and a trapping dipole force, plus a quantized light to rque associated with the orbital angular momentum property of excited waveg uide modes of order l > 0. It is predicted that in addition to its axial mo tion, an atom subject to such a mode should be trapped radially in a vibrat ional state and should exhibit interesting rotational features due to the l ight torque, including a rotational frequency shift.