Degree of Entanglement and Violation of Bell Inequality by Two-Spin-1/2 States

• 来源期刊: 理论物理通讯：英文版
• 学科: 物理学
• 关键词: 贝尔不等式 纠缠态 双自旋 学位 混合态 量子力学 复合系统 量子比特
• 年，卷（期）: 2011,（10）
• 页码范围: 679-686
• 页数: 8页
• 分类号: O413.1|V474.24
• 语种: 英文

摘要

Bell inequality is violated by the quantum mechanical predictions made from an entangled state of the composite system. In this paper we examine this inequality and entanglement measures in the construction of the coherent states for two-qubit pure and mixed states, we find a link to some entanglement measures through some new parameters （amplitudes of coherent states）. Conditions for maximal entanglement and separability are then established for both pure and mixed states. Finally, we analyze and compare the violation of Bell inequality for a class of mixed states with the degree of entanglement by applying the formalism of Horodecki et al.