Bell-correlated activable bound entanglement in multiqubit systems
Somshubhro Bandyopadhyay, Indrani Chattopadhyay, Vwani Roychowdhury, Debasis Sarkar · Physical Review A · 2005
We show that the Hilbert space of even number $(\ensuremath{\geqslant}4)$ 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.