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AIP conference proceedings

Ultracold atoms on atom chips: Manipulation at the μm distance scale

P. Krüger

Published Jan 1, 2005• 1 citation
Publisher

Abstract

Miniaturized potentials near the surface of atom chips can be used as flexible and versatile tools for the manipulation of ultracold atoms on a microscale. The full scope of possibilities is only accessible if atom‐surface distances can be reduced to microns. We discuss experiments in this regime and potential obstacles and solutions. We show that appropriate fabrication techniques lead to a reduction of disorder potentials so that one‐dimensional condensates can be prepared. We demonstrate how electrostatic potentials can be used to modify magnetic trapping potentials and how they can be used to study condensate formation in situations of different dimensionality.

DOI
10.1063/1.1928849

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Miniaturized potentials near the surface of atom chips can be used as flexible and versatile tools for the manipulation of ultracold atoms on a microscale. The full scope of possibilities is only accessible if atom‐surface distances can be reduced to microns. We discuss experiments in this regime and potential obstacles and solutions. We show that appropriate fabrication techniques lead to a reduction of disorder potentials so that one‐dimensional condensates can be prepared. We demonstrate how electrostatic potentials can be used to modify magnetic trapping potentials and how they can be used to study condensate formation in situations of different dimensionality.
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Trapping and manipulating ultracold atoms and degenerate quantum gases in magnetic micropotentials is reviewed. Starting with a comprehensive description of the basic concepts and fabrication techniques of microtraps together with early pioneering experiments, emphasis is placed on current experiments on degenerate quantum gases. This includes the loading of quantum gases in microtraps, coherent manipulation, and transport of condensates together with recently reported experiments on matter-wave interferometry on a chip. Theoretical approaches for describing atoms in waveguides and beam splitters are briefly summarized, and, finally, the interaction between atoms and the surface of microtraps is covered in some detail.