Numerical evaluation of convex-roof entanglement measures with applications to spin rings

@article{Rothlisberger2009NumericalEO,
  title={Numerical evaluation of convex-roof entanglement measures with applications to spin rings},
  author={Beat Rothlisberger and Jorg Lehmann and Daniel Loss},
  journal={Physical Review A},
  year={2009},
  volume={80}
}
We present two ready-to-use numerical algorithms to evaluate convex-roof extensions of arbitrary pure-state entanglement monotones. Their implementation leaves the user merely with the task of calculating derivatives of the respective pure-state measure. We provide numerical tests of the algorithms and demonstrate their good convergence properties. We further employ them in order to investigate the entanglement in particular few-spins systems at finite temperature. Namely, we consider… 

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