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Connecting the generalized robustness and the geometric measure of entanglement

Daniel Cavalcanti
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Abstract

The main goal of this paper is to provide a connection between the generalized robustness of entanglement ($R_g$) and the geometric measure of entanglement ($E_{GME}$). First, we show that the generalized robustness is always higher than or equal to the geometric measure. Then we find a tighter lower bound to $R_g(ρ)$ based only on the purity of $ρ$ and its maximal overlap to a separable state. As we will see it is also possible to express this lower bound in terms of $E_{GME}$.

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Daniel Cavalcanti. 2008-01-07. Connecting the generalized robustness and the geometric measure of entanglement. https://doi.org/10.1103/physreva.73.044302

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