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Title: Coherent control in a decoherence-free subspace of a collective multilevel system

Abstract

Decoherence-free subspaces (DFS's) in systems of dipole-dipole interacting multilevel atoms are investigated theoretically. It is shown that the collective state space of two dipole-dipole interacting four-level atoms contains a four-dimensional DFS. We describe a method that allows us to populate the antisymmetric states of the DFS by means of a laser field, without the need for a field gradient between the two atoms. We identify these antisymmetric states as long-lived entangled states. Further, we show that any single-qubit operation between two states of the DFS can be induced by means of a microwave field. Typical operation times of these qubit rotations can be significantly shorter than for a nuclear spin system.

Authors:
; ;  [1]
  1. Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany)
Publication Date:
OSTI Identifier:
20982259
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 75; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevA.75.032313; (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; CONTROL THEORY; DIPOLES; FOUR-DIMENSIONAL CALCULATIONS; LASER RADIATION; MICROWAVE RADIATION; PHOTON-ATOM COLLISIONS; QUANTUM DECOHERENCE; QUANTUM ENTANGLEMENT; QUANTUM MECHANICS; QUBITS; ROTATION; SPIN

Citation Formats

Kiffner, M., Evers, J., and Keitel, C. H. Coherent control in a decoherence-free subspace of a collective multilevel system. United States: N. p., 2007. Web. doi:10.1103/PHYSREVA.75.032313.
Kiffner, M., Evers, J., & Keitel, C. H. Coherent control in a decoherence-free subspace of a collective multilevel system. United States. doi:10.1103/PHYSREVA.75.032313.
Kiffner, M., Evers, J., and Keitel, C. H. Thu . "Coherent control in a decoherence-free subspace of a collective multilevel system". United States. doi:10.1103/PHYSREVA.75.032313.
@article{osti_20982259,
title = {Coherent control in a decoherence-free subspace of a collective multilevel system},
author = {Kiffner, M. and Evers, J. and Keitel, C. H.},
abstractNote = {Decoherence-free subspaces (DFS's) in systems of dipole-dipole interacting multilevel atoms are investigated theoretically. It is shown that the collective state space of two dipole-dipole interacting four-level atoms contains a four-dimensional DFS. We describe a method that allows us to populate the antisymmetric states of the DFS by means of a laser field, without the need for a field gradient between the two atoms. We identify these antisymmetric states as long-lived entangled states. Further, we show that any single-qubit operation between two states of the DFS can be induced by means of a microwave field. Typical operation times of these qubit rotations can be significantly shorter than for a nuclear spin system.},
doi = {10.1103/PHYSREVA.75.032313},
journal = {Physical Review. A},
number = 3,
volume = 75,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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