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On the Entangling Power of Quantum Evolutions

Paolo Zanardi·Christof Zalka·Lara Faoro
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Abstract

We analyze the entangling capabilities of unitary transformations $U$ acting on a bipartite $d_1\times d_2$-dimensional quantum system. To this aim we introduce an entangling power measure $e(U)$ given by the mean linear entropy produced acting with $U$ on a given distribution of pure product states. This measure admits a natural interpretation in terms of quantum operations. For a uniform distribution explicit analytical results are obtained using group-theoretic arguments. The behaviour of the features of $e(U)$ as the subsystem dimensions $d_1$ and $d_2$ are varied is studied both analytically and numerically. The two-qubit case $d_1=d_2=2$ is argued to be peculiar.

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Paolo Zanardi, Christof Zalka, Lara Faoro. 2000-05-08. On the Entangling Power of Quantum Evolutions. https://doi.org/10.1103/physreva.62.030301

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