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arXiv · 1601.05008

Transport dynamics of ultracold atoms in a triple-well transistor-like potential

Seth C. Caliga·Cameron J. E. Straatsma·Dana Z. Anderson
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Abstract

The transport of atoms is experimentally studied in a transistor-like triple-well potential consisting of a narrow gate well surrounded by source and drain wells. Atoms are initially loaded into the source well with pre-determined temperature and chemical potential. Energetic atoms flow from the source, across the gate, and into the drain where they are removed using a resonant light beam. The manifestation of atom-atom interactions and dissipation is evidenced by a rapid population growth in the initially vacant gate well. The transport dynamics are shown to depend strongly on a feedback parameter determined by the relative heights of the two barriers forming the gate region. For a range of feedback parameter values, experiments establish that the gate atoms develop a larger chemical potential and lower temperature than those in the source.

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Seth C. Caliga, Cameron J. E. Straatsma, Dana Z. Anderson. 2016-01-19. Transport dynamics of ultracold atoms in a triple-well transistor-like potential. https://doi.org/10.1088/1367-2630%2F18%2F2%2F025010

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