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Euclidean volume ratios of separable and entangled states in two-qubit and qubit-qutrit systems

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 Publication date 2021
  fields Physics
and research's language is English




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Euclidean volume ratios characterizing the typicality of entangled and separable states are investigated for two-qubit and qubit-qutrit quantum states. For this purpose a new numerical approach is developed. It is based on the Peres-Horodecki criterion, on a characterization of the convex set of quantum states by inequalities resulting from Newton identities and Descartes rule of signs and on combining this characterization with standard and Multiphase Monte Carlo algorithms. Our approach confirms not only recent results on two-qubit states but also allows for a numerically reliable numerical treatment of so far unexplored special classes of two-qubit and qubit-qutrit states. However, our results also hint at the limits of efficiency of our numerical Monte Carlo approaches which is already marked by the most general qubit-qutrit states forming a convex set in a linear manifold of thirtyfive dimensions.



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