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Title: Universal quantum computation in a neutral-atom decoherence-free subspace

Abstract

In this paper, we propose a way to achieve protected universal computation in a neutral-atom quantum computer subject to collective dephasing. Our proposal relies on the existence of a decoherence-free subspace (DFS), resulting from symmetry properties of the errors. After briefly describing the physical system and the error model considered, we show how to encode information into the DFS and build a complete set of safe universal gates. Finally, we provide numerical simulations for the fidelity of the different gates in the presence of time-dependent phase errors and discuss their performance and practical feasibility.

Authors:
; ; ; ;  [1];  [2]
  1. Lundbeck Foundation Theoretical Center for Quantum System Research, Department of Physics and Astronomy, University of Aarhus, Ny Munkegade, Building 1520, DK-8000 Arhus C (Denmark)
  2. (United States)
Publication Date:
OSTI Identifier:
20982274
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 75; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevA.75.032328; (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; CALCULATION METHODS; ERRORS; INFORMATION THEORY; QUANTUM COMPUTERS; QUANTUM DECOHERENCE; RUBIDIUM; SIMULATION; SYMMETRY; TIME DEPENDENCE

Citation Formats

Brion, E., Pedersen, L. H., Moelmer, K., Chutia, S., Saffman, M., and Department of Physics, University of Wisconsin, 1150 University Avenue, Madison, Wisconsin 53706. Universal quantum computation in a neutral-atom decoherence-free subspace. United States: N. p., 2007. Web. doi:10.1103/PHYSREVA.75.032328.
Brion, E., Pedersen, L. H., Moelmer, K., Chutia, S., Saffman, M., & Department of Physics, University of Wisconsin, 1150 University Avenue, Madison, Wisconsin 53706. Universal quantum computation in a neutral-atom decoherence-free subspace. United States. doi:10.1103/PHYSREVA.75.032328.
Brion, E., Pedersen, L. H., Moelmer, K., Chutia, S., Saffman, M., and Department of Physics, University of Wisconsin, 1150 University Avenue, Madison, Wisconsin 53706. Thu . "Universal quantum computation in a neutral-atom decoherence-free subspace". United States. doi:10.1103/PHYSREVA.75.032328.
@article{osti_20982274,
title = {Universal quantum computation in a neutral-atom decoherence-free subspace},
author = {Brion, E. and Pedersen, L. H. and Moelmer, K. and Chutia, S. and Saffman, M. and Department of Physics, University of Wisconsin, 1150 University Avenue, Madison, Wisconsin 53706},
abstractNote = {In this paper, we propose a way to achieve protected universal computation in a neutral-atom quantum computer subject to collective dephasing. Our proposal relies on the existence of a decoherence-free subspace (DFS), resulting from symmetry properties of the errors. After briefly describing the physical system and the error model considered, we show how to encode information into the DFS and build a complete set of safe universal gates. Finally, we provide numerical simulations for the fidelity of the different gates in the presence of time-dependent phase errors and discuss their performance and practical feasibility.},
doi = {10.1103/PHYSREVA.75.032328},
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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