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Modular construction of special mixed quantum states

  • M. MichelEmail author
  • G. Mahler
OriginalPaper
  • 31 Downloads

Abstract.

For a homogeneous quantum network of N subsystems with n levels each we consider separable generalized Werner states. A generalized Werner state is defined as a mixture of the totally mixed state and an arbitrary pure state \(\vert\psi\rangle\): \(\hat{p}_{Werner} = (1-\epsilon)\hat{1}+\epsilon\vert\psi\rangle\langle\psi\vert\) with a mixture coefficient \(\epsilon\). For this density operator \(\hat{p}_{Werner}\) to be separable, \(\epsilon\) will have an upper bound \(\epsilon_{sep}\leq1\). Below this bound one should alternatively be able to reproduce \(\hat{p}_{Werner}\) by a mixture of entirely separable input-states. For this purpose we introduce a set of modules, each contributing elementary coherence properties with respect to a generalized coherence vector. Based on these there exists a general step-by-step mixing process for any \(\epsilon_{mix}\leq\epsilon_{max}\). For \(\vert\psi\rangle\) being a cat-state it is possible to define an optimal process, which produces states right up to the separability boundary ( \(\epsilon_{max} = \epsilon_{sep} \)).

Keywords

Coherence Optimal Process Quantum State Mixed State Pure State 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag Berlin/Heidelberg 2003

Authors and Affiliations

  1. 1.Institute of Theoretical Physics IUniversity of StuttgartStuttgartGermany

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