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Adapted-operator representations: Selective versus collective properties of quantum networks

Alexander Otte·Guenter Mahler
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Abstract

Based on local unitary operators acting on a n-dimensional Hilbert-space, we investigate selective and collective operator basis sets for N-particle quantum networks. Selective cluster operators are used to derive the properties of general cat-states for any n and N. Collective operators are conveniently used to account for permutation symmetry: The respective Hilbert-space dimension is then only polynomial in N and governed by strong selection rules. These selection rules can be exploited for the design of decoherence-free subspaces as well as for the implementation of efficient routes to entanglement if suspended switching between states of different symmetry classes could be realized.

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Alexander Otte, Guenter Mahler. 2001-01-30. Adapted-operator representations: Selective versus collective properties of quantum networks. https://doi.org/10.1103/physreva.62.012303

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