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arXiv · 1512.01989

Quantum correlations of identical particles subject to classical environmental noise

Andrea Beggi·Fabrizio Buscemi·Paolo Bordone
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Abstract

In this work we propose a measure for the quantum discord of indistinguishable particles, based on the definition of entanglement of particles given in [H. M. Wiseman et al., Phis. Rev. Lett 91, 097902 (2003)]. This discord of particles is then used to evaluate the quantum correlations in a system of two identical bosons (fermions), where the particles perform a quantum random walk described by the Hubbard hamiltonian in a 1D lattice. The dynamics of the particles is either unperturbed or subject to a classical environmental noise - such as random telegraph, pink or brown noise. The observed results are consistent with those for the entanglement of particles, and we observe that on-site interaction between particles have an important protective effect on correlations against the decoherence of the system.

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Andrea Beggi, Fabrizio Buscemi, Paolo Bordone. 2016-04-27. Quantum correlations of identical particles subject to classical environmental noise. https://doi.org/10.1007/s11128-016-1334-8

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