We describe an experiment in which Bose-Einstein condensates and cold atom clouds are held by a microscopic magnetic trap near a room temperature metal wire 500 μm in diameter. The ensemble of atoms breaks into fragments when it is brought close to the ceramic-coated aluminum surface of the wire, showing that fragmentation is not peculiar to copper surfaces. The lifetime for atoms to remain in the microtrap is measured over a range of distances down to 27μm from the surface of the metal. We observe the loss of atoms from the microtrap due to spin flips. These are induced by radio-frequency thermal fluctuations of the magnetic field near the surface, as predicted but not previously observed.
@article{arxiv.quant-ph/0301018,
title = {Thermally induced spin flips above an atom chip},
author = {M. P. A. Jones and C. J. Vale and D. Sahagun and B. V. Hall and E. A. Hinds},
journal= {arXiv preprint arXiv:quant-ph/0301018},
year = {2013}
}