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Title: Magnetic microtraps for ultracold atoms

Abstract

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.

Authors:
;  [1]
  1. Physikalisches Institut, Universitaet Tuebingen, Auf der Morgenstelle 14, 72076 Tuebingen (Germany)
Publication Date:
OSTI Identifier:
21013703
Resource Type:
Journal Article
Resource Relation:
Journal Name: Reviews of Modern Physics; Journal Volume: 79; Journal Issue: 1; Other Information: DOI: 10.1103/RevModPhys.79.235; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ATOMS; GASES; INTERACTIONS; INTERFEROMETRY; MATTER; RADIATION PRESSURE; TRANSPORT THEORY; TRAPPING; WAVEGUIDES

Citation Formats

Fortagh, Jozsef, and Zimmermann, Claus. Magnetic microtraps for ultracold atoms. United States: N. p., 2007. Web. doi:10.1103/REVMODPHYS.79.235.
Fortagh, Jozsef, & Zimmermann, Claus. Magnetic microtraps for ultracold atoms. United States. doi:10.1103/REVMODPHYS.79.235.
Fortagh, Jozsef, and Zimmermann, Claus. Mon . "Magnetic microtraps for ultracold atoms". United States. doi:10.1103/REVMODPHYS.79.235.
@article{osti_21013703,
title = {Magnetic microtraps for ultracold atoms},
author = {Fortagh, Jozsef and Zimmermann, Claus},
abstractNote = {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.},
doi = {10.1103/REVMODPHYS.79.235},
journal = {Reviews of Modern Physics},
number = 1,
volume = 79,
place = {United States},
year = {Mon Jan 15 00:00:00 EST 2007},
month = {Mon Jan 15 00:00:00 EST 2007}
}
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  • Recently demonstrated superconducting atom chips provide a platform for trapping atoms and coupling them to solid-state quantum systems. Controlling these devices requires a full understanding of the supercurrent distribution in the trapping structures. For type-II superconductors, this distribution is hysteretic in the critical state due to the partial penetration of the magnetic field in the thin superconducting film through pinned vortices. We report here an experimental observation of this memory effect. Our results are in good agreement with the predictions of the Bean model of the critical state without adjustable parameters. The memory effect allows to write and store permanentmore » currents in micron-sized superconducting structures and paves the way toward engineered trapping potentials.« less
  • We derive a model to describe decoherence of atomic clouds in atom-chip traps taking the excited states of the trapping potential into account. We use this model to investigate decoherence for a single trapping well and for a pair of trapping wells that form the two arms of an atom interferometer. Including the discrete spectrum of the trapping potential gives rise to a decoherence mechanism with a decoherence rate {gamma} that scales like {gamma}{approx}1/r{sub 0}{sup 4} with the distance r{sub 0} from the trap minimum to the wire.