Phys. Rev. A 81, 063808 (2010)

SCI

Motion of an atom in a weakly driven fiber-Bragg-grating cavity: Force, friction, and diffusion

Fam Le Kien and K. Hakuta

We study the translational motion of an atom in the vicinity of a weakly driven nanofiber with two fiber-Bragggrating mirrors.We calculate numerically and analytically the force, the friction coefficients, and the momentum diffusion.We find that the spatial dependences of the force, the friction coefficients, and the momentum diffusion are very complicated due to the evanescent-wave nature of the atom-field coupling as well as the effect of the van der Waals potential. We show that the time development of the mean number of photons in the cavity closely follows the translational motion of the atom through the nodes and antinodes of the fiber-guided cavity standing-wave field even though the cavity finesse is moderate, the cavity is long, and the probe field is weak