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Bell-Correlated Activable Bound Entanglement in Multiqubit Systems

Somshubhro Bandyopadhyay·Indrani Chattopadhyay·Vwani P. Roychowdhury·Debasis Sarkar
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Abstract

We show that the Hilbert space of even number ($\geq4$) of qubits can always be decomposed as a direct sum of four orthogonal subspaces such that the normalized projectors onto the subspaces are activable bound entangled (ABE) states. These states also show a surprising recursive relation in the sense that the states belonging to $2N+2$ qubits are Bell correlated to the states of $2N$ qubits; hence, we refer to these states as Bell-Correlated ABE (BCABE) states. We also study the properties of noisy BCABE states and show that they are very similar to that of two qubit Bell-diagonal states.

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Somshubhro Bandyopadhyay, Indrani Chattopadhyay, Vwani P. Roychowdhury, Debasis Sarkar. 2004-11-11. Bell-Correlated Activable Bound Entanglement in Multiqubit Systems. https://doi.org/10.1103/physreva.71.062317

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