Scattering of ultracold atoms by a single nanotube |
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| Martin Fink | |
| Technische Universität München | |
| As an example of a hybrid quantum system containing atoms at low temperatures and macro- or mesoscopic structures on the nanometer scale, we study the dynamics of a fundamental quasi two-dimensional system consisting of an ultracold atom and a perfectly absorbing nanotube of infinite length. We derive an accurate approximation to the atom-wire potential, based on exact expressions in the non-retarded and in the highly-retarded limits. With this potential we can numerically calculate the scattering properties, e.g. scattering length, elastic and absorption cross section. In realistic cases, the results are close to the expectations for the highly retarded limit of the potential. Comparing the scattering of ultracold atoms to the scattering of electromagnetic waves by a cylinder, we can identify an electromagnetic and a non-electromagnetic limit of the system which are both accessible for experimental setups. This is the first microscopically founded realistic analysis of the scattering of ultracold atoms by a single nanotube and contributes to the understanding of more complex systems like nanogratings that are used in diffraction and interference experiments. |