普通型Bell多项式及其矩阵

给出了普通型Bell多项式的性质, 得到了普通型Bell多项式矩阵的分解.求出了Bell多项式矩阵与Fibonacci矩阵之间的关系, 进而得到了普通型Bell多项式与Fibonacci数之间的关系.     

C~2C~3中Bell基型不可拓展的最大纠缠基和互不偏基

先在C2C3中得到一组Bell基型完备的不可拓展的最大纠缠基,再通过构造C3的一个标准正交基给出另一组Bell基型完备的不可拓展的最大纠缠基,同时保证这两组基是互不偏的,并给出两类Bell基型互不偏的不可拓展的最大纠缠基.     

Bell不等式的失败根源和对定域性原则的直接检验

本文考查了各种Bell不等式的理论推导和实验检验方法,分析了不等式失败的原因,指出:双值自旋粒子系、严格的关联条件和定域性原则都是导致Bell型不等式与实验相悖的可能因素。以往的检验实验不足以否定定域性原则。为了单独地直接检验定域性原则,文中提出了一个新型不等式。     

普通型Bell多项式与卷积多项式序列的若干恒等式

应用发生函数的方法研究了与卷积型多项式序列有关的普通型Bell多项式,得到了关于普通型Bell多项式的若干恒等式。     

利用线性元件实现完全Bell态测量

.Bell态测量是量子信息研究中的重要组成部分.之前的研究表明,只基于线性光学操作不能实现完全Bell态测量,但通过引入辅助光子对或多自由度,可以提高Bell态的区分效率.文章利用混合分束器耦合不同的自由度可以将普通分束器不能区分的两个Bell态分辨出来的作用,提出一种新的Bell态测量方案:在对待测Bell态成功制备...     

运用扩展的Bell测量实现三粒子任意态的量子隐形传态

提出一种运用扩展的Bell测量实现三粒子任意态的量子隐形传态方案,构建了64种正交的扩展Bell态,运用一个最大纠缠的六粒子量子态作为量子通道,在相互的经典通信和一些相应的单粒子幺正变换的协助下,信息的接受者Bob成功恢复了初始量子态,成功传态的总概率为1．     

关于Bell数的几个不等式

本文主要研究了相邻两个Bell数之间的关系,由此得出了一些有关Bell数上下界的不等式。     

运用简化的Bell基测量实现多粒子隐形传态

采用一种新的多粒子隐形传态方案。传态过程,利用与Rigolin方案中相似的量子通道,无需复杂的扩展Bell测量,而是使用了实验上容易实现的Bell测量作为手段。同时构建了一个共同的幺正矩阵来提取所有可能塌缩态的最小系数。整体成功传态的概率为|b1/2(2~(1/2))|2。     

Bell不等式及其局域性假设

文中首先证明Bell不等式成立的充足条件是几率的Kolmogorov模型.不等式破缺只说明对量子关联系统Kolmogorov模型失效.其次,Bell的局域性假设不能与 Einstein 的“分离性”条件等价,它隐含有苛刻的几率约束条件,最后指出了 Bell 不等式也不是完全地符合量子理论的预测.因此,量子理论基础问题的讨论,并没有由于 Bell 不等式的实验验证作出判决.     

基于一个共享辅助逻辑Bell态的抗集体噪声鲁棒量子对话

本文分别提出两个抵抗集体退相位噪声和集体旋转噪声的鲁棒量子对话(Quantum Dialogue,QD)协议.在每个提出的QD协议中,每个由4物理量子比特构成的4个逻辑Bell态被用于对抗集体噪声.信息泄露问题通过从一个通信方向另一个通信方直接两步传送辅助逻辑Bell态来克服.Bell态测量而非4量子比特联合测量被用于解码.抵抗窃听者主动攻击(如截获-重发攻击、测量-重发攻击、纠缠-测量攻击和木马攻击)的有效性能够得到保证.     

利用光子纠缠混合态实现Bell不等式检验

Bell不等式的违背是量子非局域关联存在的重要证据之一.利用各种纠缠源,人们已经在多个实验中实现了这种违背的验证.然而,最优的违背（即Cirel’son极限）仍未能在实验上达到.针对其中的两种可能的原因：所使用纠缠源的纠缠度难以达到最大纠缠或者所选取的测量基并非是最优测量基;本文利用商用光子纠缠源在实验上探索这一问题的可能解决方案.我们首先在实验上验证了,基于通常两体光子纠缠纯态假定所选取的测量基并不能得到Bell不等式的最佳违背.利用量子态层析技术,我们重构了该商用纠缠光子态的密度矩阵,并证实了实验中所用的纠缠光源是一个混合纠缠态.据此,我们对测量基进行了优化,明显地提高了Bell不等式的违背程度.     

Bell inequality,separability and entanglement distillation

In this review,we introduce well-known Bell inequalities,the relations between the Bell inequality and quantum separability,and the entanglement distillation of quantum states.It is shown that any pure entangled quantum state violates one of Bell-like inequalities.Moreover,quantum states that violate any one of these Bell-like inequalities are shown to be distillable.New Bell inequalities that detect more entangled mixed states are also introduced.     

Characterization of four-qubit states via Bell inequalities

A set of Bell inequalities classifying the quantum entanglement of four-qubit states is presented. These inequalities involve only two measurement settings per observer and can characterize fully separable, bi-separable and tri-separable quantum states. In addition, a quadratic inequality of the Bell operators for four-qubit systems is derived.     

Bell不等式及其意义

本文针对文献［３］关于隐变量理论及Ｂｅｌｌ不等式证明过程不清楚地方作了详细的讨论，并说明了其意义．     

Bell不等式及其意义

本文针对文献关于隐变量理论及Bell不等式证明过程不清楚地方作了详细的讨论,并说明了其意义。     

违犯Bell不等式的正交态及非正交态的量子缠绕

给出正交态及非正交态的量子缠绕，通过分析两个实例．发现能够产生不遵守Bell不等式最大限度的缠绕态．     

双模减单光子压缩真空态的量子退相干和非局域性动力学

本文研究了双模减单光子压缩真空态的量子退相干和非局域性动力学．数值计算了相对熵纠缠度和计算分析了线性熵纠缠度．并进一步计算了基于膺自旋算符的Bell不等式，发现Bell不等式总是违背的．因此，可以确定退相干只能减少双模减单光子压缩真空态的纠缠量，不能完全消除纠缠．     

Testing the speed of 'spooky action at a distance'

Correlations are generally described by one of two mechanisms: either a first event influences a second one by sending information encoded in bosons or other physical carriers, or the correlated events have some common causes in their shared history. Quantum physics predicts an entirely different kind of cause for some correlations, named entanglement. This reveals itself in correlations that violate Bell inequalities (implying that they cannot be described by common causes) between space-like separated events (implying that they cannot be described by classical communication). Many Bell tests have been performed, and loopholes related to locality and detection have been closed in several independent experiments. It is still possible that a first event could influence a second, but the speed of this hypothetical influence (Einstein's 'spooky action at a distance') would need to be defined in some universal privileged reference frame and be greater than the speed of light. Here we put stringent experimental bounds on the speed of all such hypothetical influences. We performed a Bell test over more than 24 hours between two villages separated by 18 km and approximately east-west oriented, with the source located precisely in the middle. We continuously observed two-photon interferences well above the Bell inequality threshold. Taking advantage of the Earth's rotation, the configuration of our experiment allowed us to determine, for any hypothetically privileged frame, a lower bound for the speed of the influence. For example, if such a privileged reference frame exists and is such that the Earth's speed in this frame is less than 10(-3) times that of the speed of light, then the speed of the influence would have to exceed that of light by at least four orders of magnitude.     

Experimental violation of a Bell's inequality with efficient detection

Local realism is the idea that objects have definite properties whether or not they are measured, and that measurements of these properties are not affected by events taking place sufficiently far away. Einstein, Podolsky and Rosen used these reasonable assumptions to conclude that quantum mechanics is incomplete. Starting in 1965, Bell and others constructed mathematical inequalities whereby experimental tests could distinguish between quantum mechanics and local realistic theories. Many experiments have since been done that are consistent with quantum mechanics and inconsistent with local realism. But these conclusions remain the subject of considerable interest and debate, and experiments are still being refined to overcome 'loopholes' that might allow a local realistic interpretation. Here we have measured correlations in the classical properties of massive entangled particles (9Be+ ions): these correlations violate a form of Bell's inequality. Our measured value of the appropriate Bell's 'signal' is 2.25 +/- 0.03, whereas a value of 2 is the maximum allowed by local realistic theories of nature. In contrast to previous measurements with massive particles, this violation of Bell's inequality was obtained by use of a complete set of measurements. Moreover, the high detection efficiency of our apparatus eliminates the so-called 'detection' loophole.     

Minty与Stampacchia向量似变分不等式

讨论两类向量似变分不等式解的关系问题,指出当定义在不变凸集上的映射是不变伪单调连续时,Minty(强)弱向量似变分不等式的解和Stampacchia(强)弱向量似变分不等式的解相同.尤其当定义在不变凸集上的矩阵映射是广义不变伪单调连续时,Minty强向量似变分不等式的解和Stampacchia向量似变分不等式的解相同.