Ground-state entanglement of the BCS model

被引：32

作者：

Dunning, C ^{[1
]}

Links, J ^{[1
]}

Zhou, HQ ^{[1
]}

机构：

[1] Univ Queensland, Ctr Math Phys, Sch Phys Sci, Brisbane, Qld 4072, Australia

来源：

PHYSICAL REVIEW LETTERS | 2005年 / 94卷 / 22期

关键词：

D O I：

10.1103/PhysRevLett.94.227002

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

The concept of local concurrence is used to quantify the entanglement between a single qubit and the remainder of a multiqubit system. For the ground state of the BCS model in the thermodynamic limit the set of local concurrences completely describes the entanglement. As a measure for the entanglement of the full system we investigate the average local concurrence (ALC). We find that the ALC satisfies a simple relation with the order parameter. We then show that for finite systems with a fixed particle number, a relation between the ALC and the condensation energy exposes a threshold coupling. Below the threshold, entanglement measures besides the ALC are significant.

引用

页数：4

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