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arXiv · 1311.2638

Recurrent construction of optimal entanglement witnesses for 2N qubit systems

Justyna P. Zwolak·Dariusz Chruściński
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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 new 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 new family of PPT (Positive Partial Transpose) entangled states.

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Justyna P. Zwolak, Dariusz Chruściński. 2013-11-11. Recurrent construction of optimal entanglement witnesses for 2N qubit systems. https://doi.org/10.1103/physreva.89.052314

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