• Corpus ID: 199472734

# Representations of two-qubit and ququart states via discrete Wigner functions

@article{Marchiolli2019RepresentationsOT,
title={Representations of two-qubit and ququart states via discrete Wigner functions},
author={Marcelo Aparecido Marchiolli and Di{\'o}genes Galetti},
journal={arXiv: Quantum Physics},
year={2019}
}
• Published 7 August 2019
• Mathematics
• arXiv: Quantum Physics
By means of a well-grounded mapping scheme linking Schwinger unitary operators and generators of the special unitary group $\mathrm{SU(N)}$, it is possible to establish a self-consistent theoretical framework for finite-dimensional discrete phase spaces which has the discrete $\mathrm{SU(N)}$ Wigner function as a legitimate by-product. In this paper, we apply these results with the aim of putting forth a detailed study on the discrete $\mathrm{SU(2)} \otimes \mathrm{SU(2)}$ and $\mathrm{SU(4… ## Figures and Tables from this paper ## References SHOWING 1-10 OF 82 REFERENCES Geometrical meaning of two-qubit entanglement and its symmetries • Physics • 2010 For pure and mixed two-qubit states we present an analysis based on symmetries of vectors and matrices associated to the density operator. These symmetries are revealed by doing reflection operations On the quantum discord of general X states It is found that the transitions between Q_{\theta }$\$Qθ subdomains occur suddenly, but continuously and smoothly, i.e., nonanalyticity is hidden and can be observed in higher order derivatives of discord function.
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