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991.
In the last decade, much attention has been focused on examining the nonlocality of various quantum networks, which are fundamental for long-distance quantum communications. In this paper, we consider the nonlocality of any forked tree-shaped network, where each node, respectively, shares arbitrary number of bipartite sources with other nodes in the next “layer”. The Bell-type inequalities for such quantum networks are obtained, which are, respectively, satisfied by all -local correlations and all local correlations, where denotes the total number of nodes in the network. The maximal quantum violations of these inequalities and the robustness to noise in these networks are also discussed. Our network can be seen as a generalization of some known quantum networks. 相似文献
992.
针对超表面在透镜方面的应用, 本文设计了一种交叉极化透射聚焦超表面, 实现了将圆极化波转化为交叉极化波的同时聚焦电磁波的功能. 设计了一款旋转型单元, 单元为一层且厚度仅为1.5 mm, 分析了旋转型单元提供不同相移的原理并设计了相邻单元相移差为60°的相位梯度超表面, 在中心频率f=15 GHz附近发生奇异折射, 折射角与理论计算结果一致, 验证了设计单元的有效性, 基于该单元设计了尺寸为90 m mm×90 mm、单元数为15×15 的透射型聚焦超表面, 在中心频率f=15 GHz附近, 左旋圆极化平面波照射时, 透射波聚焦于L=40 mm 的实焦点且透射波为照射波的交叉极化波. 该超表面透镜效率高、厚度薄且为单层, 易于加工, 相对于传统透镜, 优势明显, 在操控电磁波、改善透镜性能方面有潜在应用价值. 相似文献
993.
A theoretical analysis of the pump-induced temperature change and associated thermal phase shift occurring in a fiber laser is presented. The temperature rise and thermal phase shift from the moment when pump is turned on to steady-state in fiber lasers, such as Yb-doped fiber laser, are numerical calculated.With the same parameters, the numerical solution is in good agreement with the finite-element (ANSYS software) simulation. 相似文献
994.
Go A Bay A Abe K Aihara H Anipko D Aulchenko V Aushev T Bakich AM Barberio E Belous K Bitenc U Bizjak I Blyth S Bozek A Bracko M Browder TE Chang P Chao Y Chen A Chen KF Chen WT Cheon BG Chistov R Choi Y Choi YK Cole S Dalseno J Danilov M Dash M Drutskoy A Eidelman S Epifanov D Fratina S Gabyshev N Gershon T Gokhroo G Golob B Gorisek A Ha H Hastings NC Hayasaka K Hayashii H Hazumi M Heffernan D Hokuue T Hoshi Y Hou S Hou WS Iijima T Ikado K Imoto A Inami K Ishikawa A Ishino H Itoh R Iwasaki M 《Physical review letters》2007,99(13):131802
The neutral B meson pair produced at the Upsilon(4S) should exhibit a nonlocal correlation of the type discussed by Einstein, Podolsky, and Rosen. We measure this correlation using the time-dependent flavor asymmetry of semileptonic B(0) decays, which we compare with predictions from quantum mechanics and two local realistic models. The data are consistent with quantum mechanics, and inconsistent with the other models. Assuming that some B pairs disentangle to produce B(0) and B(0) with definite flavor, we find a decoherent fraction of 0.029 +/ -0.057, consistent with no decoherence. 相似文献
995.
Lv Z Fu Y Hou S Wang D Wu H Zhang C Chu Z Zou D 《Physical chemistry chemical physics : PCCP》2011,13(21):10076-10083
A high-efficiency dye-sensitized solar cell prototype has been designed and fabricated, in which the working electrode and counter electrode are in direct contact and singly twisted. The cell is sealed in a capillary. In this solar cell configuration, the area ratio between the counter and working electrode is extremely low which allows the independent adjustment of electrolyte volume and the distance between counter electrode and photo-anode. Also it is more easily sealed compared to planar solar cell. The effects of TiO(2) film thickness, twisted pitch of counter electrode and length of device have been investigated. Our results indicate that this novel configuration has demonstrated excellent modularization function, three dimensional light harvesting capacities and the relative independence of incident light angles due to the symmetry structure. The power conversion efficiency of one cell of 9.5 cm in length can reach up to 5.41% at standard test condition (100 mW cm(-2)) and the power output may double under intense diffuse illumination. As far as we know, this is the longest and most efficient fiber-shaped dye-sensitized solar cell consisting of liquid electrolyte. The longer the fiber-shaped solar cell is, the more suitable it is for woven solar power textile if it is encapsulated in transparent flexible plastic capillary. 相似文献
996.
基于X射线衍射仪运行的稳定性和角度的精密控制能力,以平面季戊四醇(PET)晶体为样品,对晶体的积分衍射效率标定方法进行了实验研究。实验的光源是Cu靶X射线管,通过适当选取镍滤片和精细控制管电压,极大地抑制了Kβ线谱和韧致辐射,实现了Kα线能量单色化。正比计数器前端的狭缝是0.05mm,采用0.001°的步进角度对源强和Kα线衍射峰分别进行扫描。数据处理后得出在Cu的Kα线能点(8047.823eV)处,该平面PET晶体的积分衍射效率是(1.759±0.002)×10-4 rad。实验结果表明该方法可以在实验室条件下快速、方便地完成平面晶体积分衍射效率的标定。 相似文献
997.
Abe K Abe K Adachi I Ahn BS Aihara H Akatsu M Alimonti G Aoki K Asai K Asai M Asano Y Aso T Aulchenko V Aushev T Bakich AM Banas E Behari S Behera PK Beiline D Bondar A Bozek A Browder TE Casey BC Chang P Chao Y Cheon BG Choi SK Choi Y Doi Y Dragic J Eidelman S Enari Y Enomoto R Everton CW Fang F Fujii H Fujita Y Fukunaga C Fukushima M Garmash A Gordon A Gotow K Guler H Guo R Haba J Haji T Hamasaki H Hanagaki K Handa F Hara K Hara T Hastings NC Hayashi K Hayashii H Hazumi M Heenan EM Higuchi I 《Physical review letters》2001,86(15):3228-3232
We report a determination of the B(0)(d)-&B_(0)(d) mixing parameter Deltam(d) based on the time evolution of dilepton yields in Upsilon(4S) decays. The measurement is based on a 5.9 fb(-1) data sample collected by the Belle detector at KEKB. The proper-time difference distributions for same-sign and opposite-sign dilepton events are simultaneously fitted to an expression containing Deltam(d) as a free parameter. Using both muons and electrons, we obtain Deltam(d) = 0.463+/-0.008 (stat)+/-0.016 (syst) ps(-1). This is the first determination of Deltam(d) from time evolution measurements at the Upsilon(4S). We also place limits on possible CPT violations. 相似文献
998.
999.
本文首先简述了1.3μm场助TE光阴极InP(衬底)/In1-xGaxAsyP1-y(光吸收层)/InP(发射层)/Ag/CsO的工作原理,并对其能带结构进行了计算,得到了In1-xGaxAsyP1-y(光吸收层)/InP(发射层)的势垒高度、掺杂、InP发射层厚度、组份、渐变区宽度,偏压及耗尽层宽度间的定量关系。并由此出发,对光阴极各参数的设计进行了分析讨论。 相似文献
1000.