Author Affiliations
Abstract
Shandong Provincial Key Laboratory of Multi-photon Entanglement and Manipulation, Department of Physics and Electronic Science, Weifang University, Weifang 261061, China
Using the entangled two-photon systems, we experimentally demonstrate the predictions of the analog Clauser-Horne- Shimony-Holt (CHSH) inequality and investigate the robustness of the CHSH-class inequality in the bit-flip noisy environment. We obtain the experimental results of CHSH inequality and analog CHSH inequality as SCHSH=2.64±0.02 and SanalogCHSH=2.76±0.02, respectively, and prove that the analog CHSH inequality is more robust against bit-flip noise than the CHSH inequality. It provides better advantages for the experimental study and application.
光电子快报（英文版）
2017, 13(4): 318
Author Affiliations
Abstract
Key Laboratory of Multi-photon Entanglement and Manipulation of Shandong Province, Department of Physics and Electronic Science, Weifang University, Weifang 261061, China
In this paper, by using the second-order parametric down-conversion of the nonlinear crystal, the spin-1 state is simulated by the two-photon polarization entangled modes. Through adjusting the laser pulse power density, the efficiency of second-order parametric down-conversion is enhanced. The intensity of the spin-1 state is 0.5/s. The fidelity of the state is up to F=0.891±0.002, and the contrast is C=17.3. The results provide a new method for Stern-Gerlach measurement on the spin-1 system.
光电子快报（英文版）
2017, 13(1): 74
Author Affiliations
Abstract
Shandong Provincial Key Laboratory of Multi-photon Entanglement and Manipulation, Department of Physics and Electronic Science, Weifang University, Weifang 261061, China
Using spontaneous parametric down conversion, polarization post selection and coincidence counting technique, the polarization Einstein-Podolsky-Rosen (EPR) entangled states are prepared. Experimental studies on the efficiency, contrast and fidelity with different pump laser intensities are performed systematically. The results show that the pump laser intensity distinctly influences the quality of entangled photons, especially the contrast and the fidelity. On the other hand, the pump efficiency of entangled photons is almost invariable, namely the entangled source brightness increases linearly with the increase of pump laser power.
光电子快报（英文版）
2015, 11(4): 317
1 潍坊学院 山东省多光子纠缠与操纵重点实验室
2 物理与光电工程学院，山东 潍坊 261061
利用制备的三光子偏振广义Greenberger-Horne-Zeilinger纠缠态，测量了三体纠缠度、Svetlichny不等式和广义Greenberger-Horne-Zeilinger态的密度矩阵.根据密度矩阵计算了三体纠缠度，测量得到了广义Greenberger-Horne-Zeilinger纠缠态的纠缠和非定域性之间的关系.结果表明：在实验误差范围内，三体纠缠度的实验测量值和理论值一致；Svetlichny算符的期望值和理论计算结果具有较好的一致性；体系非定域特性和体系的纠缠程度密切相关，当纠缠度减小时，非定域性减弱.
量子纠缠 广义GHZ纠缠态 Svetlichny算符 非定域性 Quantum entanglement Generalized GHZ entangled states Svetlichny inequality Nonlocality
潍坊学院物理与光电工程学院, 山东省多光子纠缠与操纵重点实验室,山东 潍坊 261061
利用数值计算的方法,研究了Kerr介质腔中的J-C模型二能级原子和单模光场作用过程中信 息熵和纠缠演化,得到了Kerr效应对纠缠态纠缠性质的影响。结果表明,Kerr介质对耦合体系的纠缠 度有强烈的影响,在合适的Kerr效应下,量子态将长时间保持最大纠缠。
量子光学 纠缠度 Kerr介质 信息熵 quantum optics degree of entanglement Kerr medium information entropy
潍坊学院物理与电子科学学院，山东 潍坊 261061
计算了三体W态的Svetlichny不等式,给出了W态非定域性的解析表达式, 讨论了W态的剩余纠缠。结果表明三体W态有着独特的共生纠缠和非定域特性,为进一步研究W态各量子比特 之间的纠缠特性以及纠缠动力学提供了理论依据。
量子光学 W态 剩余纠缠 Svetlichny不等式 非定域性 quantum optics W states three body entanglement Svetlichny inequality nonlocality
潍坊学院 物理与电子科学系,山东 潍坊 2610611
采用数值计算法研究了纠缠双原子和相干光场相互作用中辐射光场光子数分布的演化特性.结果表明,通过和纠缠双原子的相互作用,使得不具有反聚束效应和光子亚泊松分布的相干光场获得了非经典特性.并且初始双原子间的纠缠强度越大,辐射光场的非经典性质越强,说明可以通过选择初始原子状态制备非经典辐射光场.
量子光学 反聚束效应 亚泊松分布 纠缠双原子 Quantum optics Anti-bunching effect Sub-Poisson distribution Entangled double atoms
曲阜师范大学物理工程学院, 山东 曲阜 273165
研究了Tavis-Cunmings模型时间演化特性和其中的光场非经典性质.精确求解了体系中光场的二阶相干函数,着重讨论了二阶相干函数和原子间耦合强度的关系.对体系可能产生的量子纠缠进行了详细的研究,在合适的初始条件下体系可以产生3bit完全纠缠态,利用Coffman对3体纠缠的定义讨论了体系3bit纠缠的纠缠度.在特定的初始条件下,体系产生W-纠缠态,给出了产生W-纠缠态的必要条件,研究了纠缠量随三体所处的初始状态、原子间及原子与场之间的耦合系数变化而变化关系.
