Pseudo-cat state

In this case, we will refer to pe as a pseudo-cat state. Generally, if p represents an entangled state, we say that Pe is pseudo-entangled. Now, if pi is a cat-state, the question is whether P( is entangled or not. We have to keep in mind that the density matrix of the whole spin system is Pe, and not p, but remember that NMR signals are proportional to pi, and not Pe. 

Benchmarking quantum control methods on a 12-qubit system - This paper was reported in 2006 by Negrevergne and co-workers [6]. It describes a benchmark experiment in which a 12 qubit pseudo-cat state was successfully produced. It is the largest NMR quantum processing experiment to date. Besides, it reaches the minimum number of qubits required to leave the separability region established by Braunstein and co-workers [1] for room-temperature liquid-state NMR. 

Applying this matrix over the pseudo-cat state results (ignoring the identity background) ... 

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