dorsal/arxiv
View SchemaTensor of coherences parameterization of multiqubit density operators for entanglement characterization
| Authors | Claudio Altafini |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0308019 |
| URL | https://arxiv.org/abs/quant-ph/0308019 |
| DOI | 10.1103/PhysRevA.69.012311 |
| Journal | Physical Review A, 69:012311, 2004 |
Abstract
For multiqubit densities, the tensor of coherences (or Stokes tensor) is a real parameterization obtained by the juxtaposition of the affine Bloch vectors of each qubit. While it maintains the tensorial structure of the underlying space, it highlights the pattern of correlations, both classical and quantum, between the subsystems and, due to the affine parameterization, it contains in its components all reduced densities of all orders. The main purpose of our use of this formalism is to deal with entanglement. For example, the detection of bipartite entanglement is straightforward, as it is the synthesis of densities having positive partial transposes between desired qubits. In addition, finding explicit mixtures for families of separable states becomes a feasible issue for few qubit symmetric densities (we compute it for Werner states) and, more important, it provides some insight on the possible origin of entanglement for such densities.
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"abstract": "For multiqubit densities, the tensor of coherences (or Stokes tensor) is a\nreal parameterization obtained by the juxtaposition of the affine Bloch vectors\nof each qubit. While it maintains the tensorial structure of the underlying\nspace, it highlights the pattern of correlations, both classical and quantum,\nbetween the subsystems and, due to the affine parameterization, it contains in\nits components all reduced densities of all orders. The main purpose of our use\nof this formalism is to deal with entanglement. For example, the detection of\nbipartite entanglement is straightforward, as it is the synthesis of densities\nhaving positive partial transposes between desired qubits. In addition, finding\nexplicit mixtures for families of separable states becomes a feasible issue for\nfew qubit symmetric densities (we compute it for Werner states) and, more\nimportant, it provides some insight on the possible origin of entanglement for\nsuch densities.",
"arxiv_id": "quant-ph/0308019",
"authors": [
"Claudio Altafini"
],
"categories": [
"quant-ph"
],
"doi": "10.1103/PhysRevA.69.012311",
"journal_ref": "Physical Review A, 69:012311, 2004",
"title": "Tensor of coherences parameterization of multiqubit density operators for entanglement characterization",
"url": "https://arxiv.org/abs/quant-ph/0308019"
},
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