Light-induced rotational effects in atom guides

摘要

We show that atomic motion in a hollow cylindrical waveguide of circular cross section is subject to a quantised torque arising from the orbital angular momentum effects associated with any excited waveguide mode of order l> 0. In addition to its axial motion due to light pressure, an appropriately detuned atom immersed in such a mode may be trapped radially in vibrational states and be made to exhibit novel rotational effects associated with the light torque, including the recently predicted rotational frequency shift.