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arXiv:1311.2638 · Physical Review A

Recurrent construction of optimal entanglement witnesses for 2N -qubit systems

Justyna P. Zwolak, Dariusz Chruściński

Published May 12, 2014• 6 citations
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Abstract

We provide a recurrent construction of entanglement witnesses for a bipartite systems living in a Hilbert space corresponding to $2N$ qubits ($N$ qubits in each subsystem). Our construction provides a method of generalization of the Robertson map that naturally meshes with $2N$-qubit systems, i.e., its structure respects the ${2}^{2N}$ growth of the state space. We prove that for $N>1$ these witnesses are indecomposable and optimal. As a byproduct we provide a family of PPT (Positive Partial Transpose) entangled states.

DOI
10.1103/physreva.89.052314

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