Entanglement and discord of the superposition of Greenberger-Horne-Zeilinger states

被引：32

作者：

Parashar, Preeti ^{[1
]}

Rana, Swapan ^{[1
]}

机构：

[1] Indian Stat Inst, Phys & Appl Math Unit, Kolkata, India

来源：

PHYSICAL REVIEW A | 2011年 / 83卷 / 03期

关键词：

RELATIVE ENTROPY;

D O I：

10.1103/PhysRevA.83.032301

中图分类号：

O43 [光学];

学科分类号：

070207 ; 0803 ;

摘要：

We calculate the analytic expression for geometric measure of entanglement for arbitrary superposition of two N-qubit canonical orthonormal Greenberger-Horne-Zeilinger (GHZ) states and the same for two W states. In the course of characterizing all kinds of nonclassical correlations, an explicit formula for quantum discord (via relative entropy) for the former class of states has been presented. Contrary to the GHZ state, the closest separable state to the W state is not classical. Therefore, in this case, the discord is different from the relative entropy of entanglement. We conjecture that the discord for the N-qubit W state is log(2) N.

引用

页数：7

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