dorsal/arxiv
View SchemaPairwise entanglement in the XX model with a magnetic impurity
| Authors | Hongchen Fu, Allan I Solomon, Xiaoguang Wang |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0201025 |
| URL | https://arxiv.org/abs/quant-ph/0201025 |
| DOI | 10.1088/0305-4470/35/19/310 |
Abstract
For a 3-qubit Heisenberg model in a uniform magnetic field, the pairwise thermal entanglement of any two sites is identical due to the exchange symmetry of sites. In this paper we consider the effect of a non-uniform magnetic field on the Heisenberg model, modeling a magnetic impurity on one site. Since pairwise entanglement is calculated by tracing out one of the three sites, the entanglement clearly depends on which site the impurity is located. When the impurity is located on the site which is traced out, that is, when it acts as an external field of the pair, the entanglement can be enhanced to the maximal value 1; while when the field acts on a site of the pair the corresponding concurrence can only be increased from 1/3 to 2/3.
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"abstract": "For a 3-qubit Heisenberg model in a uniform magnetic field, the pairwise\nthermal entanglement of any two sites is identical due to the exchange symmetry\nof sites. In this paper we consider the effect of a non-uniform magnetic field\non the Heisenberg model, modeling a magnetic impurity on one site. Since\npairwise entanglement is calculated by tracing out one of the three sites, the\nentanglement clearly depends on which site the impurity is located. When the\nimpurity is located on the site which is traced out, that is, when it acts as\nan external field of the pair, the entanglement can be enhanced to the maximal\nvalue 1; while when the field acts on a site of the pair the corresponding\nconcurrence can only be increased from 1/3 to 2/3.",
"arxiv_id": "quant-ph/0201025",
"authors": [
"Hongchen Fu",
"Allan I Solomon",
"Xiaoguang Wang"
],
"categories": [
"quant-ph"
],
"doi": "10.1088/0305-4470/35/19/310",
"title": "Pairwise entanglement in the XX model with a magnetic impurity",
"url": "https://arxiv.org/abs/quant-ph/0201025"
},
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"type": "Model",
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