We investigate theoretically how cold atoms, including Bose-Einstein
condensates, are scattered from, or absorbed by nanotubes with a view to
analysing recent experiments. In particular we consider the role of potential
strength, quantum reflection, atomic interactions and tube vibrations on atom
loss rates. Lifshitz theory calculations deliver a significantly stronger
scattering potential than that found in experiment and we discuss possible
reasons for this. We find that the scattering potential for dielectric tubes
can be calculated to a good approximation using a modified pairwise summation
approach, which is efficient and easily extendable to arbitrary geometries.
Quantum reflection of atoms from a nanotube may become a significant factor at
low temperatures, especially for non-metallic tubes. Interatomic interactions
are shown to increase the rate at which atoms are lost to the nanotube and lead
to non-trivial dynamics. Thermal nanotube vibrations do not significantly
increase loss rates or reduce condensate fractions, but lower frequency
oscillations can dramatically heat the cloud.Comment: 7 pages, 4 figure
