Separability condition for multi-mode continuous-variable systems

被引：0

作者：

School of Science, Lanzhou University of Technology, Lanzhou 730050, China ^{[1
]}

机构：

[1] School of Science, Lanzhou University of Technology

来源：

Guangxue Xuebao | 2009年 / 3卷 / 827-830期

关键词：

Cauchy-Schwarz inequality; Quantum entanglement; Separability condition; Separable states;

D O I：

10.3788/AOS20092903.0827

中图分类号：

学科分类号：

摘要：

A separability condition based on the product variance of a pair of Einstein-Podolsky-Rosen (EPR) type operators is obtained for continuous-variable systems by using Heisenberg uncertainty relation and Cauchy-Schwarz inequality. It can be used to detect the entanglement of non-Gaussian states, the entanglement of coherent state. Moreover, anther condition used to judge if quantum state gets entangled is obtained by using total variance. Two conditions were discussed contrastively were F̂j was position operator, Ĝj was momentum operator and n=2. The result shows that detection ability of the former inequality is stronger than the latter when the coefficient is satisfied with the relation of ∑|cjdj|>4.

引用

页码：827 / 830

页数：3

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