论文标题
表征纯对称三量状态的非局部性
Characterizing nonlocality of pure symmetric three-qubit states
论文作者
论文摘要
我们使用Clauser-Horne-Horne-Holt-Holt（CHSH）不等式探索了爱丽丝，鲍勃和查理之间三分之一的纯对称状态的非局部性。我们以这些状态的规范形式利用了优雅的参数化，由Meill and Meyer（Phys。Rev。A，96，062310（2017））基于Majorana几何表示。从任意的纯对称对称三分位状态中提取的降低的两分质状态并不违反CHSH不平等，因此它们是Chsh-local。然而，当爱丽丝和鲍勃进行CHSH测试时，在对查理的测量结果进行调节之后，揭示了国家的非局部性。我们还表明，可以根据条件CHSH非局部性测试中的违规强度来区分两个分别由两个和三个不同的旋转器（Qubits）组成的三量纯对称状态的不同家族。此外，我们确定了在三方，两部分，两场结果（即（3,2,2）场景中的46种紧密钟不等式中的六个（Phys。Rev.A 94，062121（2016））。在两个纯正对称状态的两个不等性家族中，只有三个不同的旋转类别类别的状态显示出对这六个紧密的铃铛不等式的最大侵犯。
We explore nonlocality of three-qubit pure symmetric states shared between Alice, Bob and Charlie using the Clauser-Horne-Shimony-Holt (CHSH) inequality. We make use of the elegant parametrization in the canonical form of these states, proposed by Meill and Meyer (Phys. Rev. A, 96, 062310 (2017)) based on Majorana geometric representation. The reduced two-qubit states, extracted from an arbitrary pure entangled symmetric three-qubit state do not violate the CHSH inequality and hence they are CHSH-local. However, when Alice and Bob perform a CHSH test, after conditioning over measurement results of Charlie, nonlocality of the state is revealed. We have also shown that two different families of three-qubit pure symmetric states, consisting of two and three distinct spinors (qubits) respectively, can be distinguished based on the strength of violation in the conditional CHSH nonlocality test. Furthermore, we identify six of the 46 classes of tight Bell inequalities in the three-party, two-setting, two-outcome i.e., (3,2,2) scenario (Phys. Rev. A 94, 062121 (2016)). Among the two inequivalent families of three-qubit pure symmetric states, only the states belonging to three distinct spinor class show maximum violations of these six tight Bell inequalities.
