dorsal/arxiv
View SchemaEntangling capacity and distinguishability of two-qubit unitary operators
| Authors | Anthony Chefles |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0502083 |
| URL | https://arxiv.org/abs/quant-ph/0502083 |
| DOI | 10.1103/PhysRevA.72.042332 |
Abstract
We prove that the entangling capacity of a two-qubit unitary operator without local ancillas, both with and without the restriction to initial product states, as quantified by the maximum attainable concurrence, is directly related to the distinguishability of a closely related pair of two-qubit unitary operators. These operators are the original operator transformed into its canonical form and the adjoint of this canonical form. The distinguishability of these operators is quantified by the minimum overlap of the output states over all possible input probe states. The entangling capacity of the original unitary operator is therefore directly related to the degree of non-Hermiticity of its canonical form, as quantified in an operationally satisfactory manner in terms of the extent to which it can be distinguished, by measurement, from its adjoint. Furthermore, the maximum entropy of entanglement, again without local ancillas, that a given two-qubit unitary operator can generate, is found to be closely related to the classical capacities of certain quantum channels.
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"abstract": "We prove that the entangling capacity of a two-qubit unitary operator without\nlocal ancillas, both with and without the restriction to initial product\nstates, as quantified by the maximum attainable concurrence, is directly\nrelated to the distinguishability of a closely related pair of two-qubit\nunitary operators. These operators are the original operator transformed into\nits canonical form and the adjoint of this canonical form. The\ndistinguishability of these operators is quantified by the minimum overlap of\nthe output states over all possible input probe states. The entangling capacity\nof the original unitary operator is therefore directly related to the degree of\nnon-Hermiticity of its canonical form, as quantified in an operationally\nsatisfactory manner in terms of the extent to which it can be distinguished, by\nmeasurement, from its adjoint. Furthermore, the maximum entropy of\nentanglement, again without local ancillas, that a given two-qubit unitary\noperator can generate, is found to be closely related to the classical\ncapacities of certain quantum channels.",
"arxiv_id": "quant-ph/0502083",
"authors": [
"Anthony Chefles"
],
"categories": [
"quant-ph"
],
"doi": "10.1103/PhysRevA.72.042332",
"title": "Entangling capacity and distinguishability of two-qubit unitary operators",
"url": "https://arxiv.org/abs/quant-ph/0502083"
},
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