dorsal/arxiv
View SchemaLocal filtering operations on two qubits
| Authors | Frank Verstraete, Jeroen Dehaene, Bart De Moor |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0011111 |
| URL | https://arxiv.org/abs/quant-ph/0011111 |
| DOI | 10.1103/PhysRevA.64.010101 |
| Journal | Physical Review A (\bf 64), 010101(R) (2001). |
Abstract
We consider one single copy of a mixed state of two qubits and investigate how its entanglement changes under local quantum operations and classical communications (LQCC) of the type $\rho'\sim (A\otimes B)\rho(A\otimes B)^{\dagger}$. We consider a real matrix parameterization of the set of density matrices and show that these LQCC operations correspond to left and right multiplication by a Lorentz matrix, followed by normalization. A constructive way of bringing this matrix into a normal form is derived. This allows us to calculate explicitly the optimal local filterin operations for concentrating entanglement. Furthermore we give a complete characterization of the mixed states that can be purified arbitrary close to a Bell state. Finally we obtain a new way of calculating the entanglement of formation.
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"abstract": "We consider one single copy of a mixed state of two qubits and investigate\nhow its entanglement changes under local quantum operations and classical\ncommunications (LQCC) of the type $\\rho\u0027\\sim (A\\otimes B)\\rho(A\\otimes\nB)^{\\dagger}$. We consider a real matrix parameterization of the set of density\nmatrices and show that these LQCC operations correspond to left and right\nmultiplication by a Lorentz matrix, followed by normalization. A constructive\nway of bringing this matrix into a normal form is derived. This allows us to\ncalculate explicitly the optimal local filterin operations for concentrating\nentanglement. Furthermore we give a complete characterization of the mixed\nstates that can be purified arbitrary close to a Bell state. Finally we obtain\na new way of calculating the entanglement of formation.",
"arxiv_id": "quant-ph/0011111",
"authors": [
"Frank Verstraete",
"Jeroen Dehaene",
"Bart De Moor"
],
"categories": [
"quant-ph"
],
"doi": "10.1103/PhysRevA.64.010101",
"journal_ref": "Physical Review A (\\bf 64), 010101(R) (2001).",
"title": "Local filtering operations on two qubits",
"url": "https://arxiv.org/abs/quant-ph/0011111"
},
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