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arXiv · 0805.2910

Collective States and Symmetric Local Decoherence in Large Ensembles of Qubits

Bradley A. Chase·J. M. Geremia
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Abstract

The symmetric collective states of an atomic spin ensemble (i.e., many-body states that are invariant under particle exchange) are not preserved by decoherence that acts identically but individually on members of the ensemble. We develop a class of collective states in an ensemble of N spin-1/2 particles that is invariant under symmetric local decoherence and find that the dimension of the Hilbert space spanned by these collective states scales only as N^2. We then investigate the open system dynamics of experimentally relevant non-classical collective atomic states, including Schroedinger cat and spin squeezed states, subject to various symmetric but local decoherence models.

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Bradley A. Chase, J. M. Geremia. 2008-05-19. Collective States and Symmetric Local Decoherence in Large Ensembles of Qubits. https://arxiv.org/abs/0805.2910

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