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991.
We present an efficient scheme for sharing an arbitrary m-qubit state with n agents. In our scheme, the sender Alice first shares m Bell states with the agent Bob, who is designated to recover the original m-qubit state. Furthermore, Alice introduces n- 1 auxiliary particles in the initial state |0), applies Hadamard (H) gate and Controlled-Not (CNOT) gate operations on the particles, which make them entangled with one of m particle pairs in Bell states, and then sends them to the controllers (i.e., other n - 1 agents), where each controller only holds one particle in hand. After Alice performing m Bell-basis measurements and each controller a single-particle measurement, the recover Bob can obtain the original unknown quantum state by applying the corresponding local unitary operations on his particles. Its intrinsic efficiency for qubits approaches 100%, and the total efficiency really approaches the maximal value. 相似文献
992.
The rare isotope ^236U has a half-life of 2.342(3)×107 years, and is produced principally by thermal neutron capture on ^235U. The isotopic atom ratio of ^236U/^238U depends on the integral thermal neutron flux received by the material of interest. ^236U is potentially useful as a "fingerprint" for indicating the presence of neutron-irradiated uranium usually originating from nuclear activity. By extracting negative molecular ion UO^- from the uranium oxide target, simulating the ^236U^16O^- beam transport with ^238U^16O^- and ^208Pb2^16O^- pilot molecular ion beam, transporting the ^236U-containing ion beam with a high resolution injection magnet analyzer and electrostatic analyzer system, and finally identifying and detecting ^236U with a time-of-flight detector (TOF), a method for AMS (Accelerator Mass Spectrometry) measurement of ^236U was established on the HI-13 Accelerator AMS system at China Institute of Atomic Energy. 相似文献
993.
The rare isotope 236U has a half-life of 2.342(3)×107 years,and is produced principally by thermal neutron capture on 235U.The isotopic atom ratio of 236U/238U depends on the integral thermal neutron flux received by the material of interest.236U is potentially useful as a fingerprint for indicating the presence of neutron-irradiated uranium usually originating from nuclear activity.By extracting negative molecular ion UO- from the uranium oxide target,simulating the 236U16O- beam transport with 238U16O- an... 相似文献
994.
A proton radiography system is an accelerator-based facility.Especially high-energy proton radiography is an advanced hydrodynamics diagnostic tool,and it is the trend of radiography technology development.In this paper,a 20 GeV accelerator complex scenario,including a 35 MeV linac,a 1 GeV booster and a 20 GeV main ring,is introduced.The overall physics design of the proton radiography accelerator is described,including the design of each part of the accelerator and the choice of the main parameters. 相似文献
995.
Improved Programming Efficiency through Additional Boron Implantation at the Active Area Edge in 90nm Localized Charge-Trapping Non-volatile Memory 下载免费PDF全文
XU Yue YAN Feng CHEN Dun-Jun SHI Yi WANG Yong-Gang LI Zhi-Guo YANG Fan WANG Jos-Hua LIN Peter CHANG Jian-Guang 《中国物理快报》2010,27(6):164-166
As the scaling-down of non-volatile memory (NVM) cells continues, the impact of shallow trench isolation (STI) on NVM cells becomes more severe. It has been observed in the 90nm localized charge-trapping non-volatile memory (NROMTM) that the programming efficiency of edge cells adjacent to STI is remarkably lower than that of other cells when channel hot electron injection is applied. Boron segregation is found to be mainly responsible for the low programming efficiency of edge cells. Meanwhile, an additional boron implantation of 10°tilt at the active area edge as a new solution to solve this problem is developed. 相似文献
996.
We consider the problem often encountered in constructing large cluster states, that is, the σx measurements in the depolarizing noise, and present a regulation to calculate the error propagation and the accumulation. Rohde et al. first pointed out the question [Phys. Rev. A 75 (2007) 010302(R)]. A quantitative analysis is given on the disadvantage influence of the probabilistic gate and noisy environment on the construction of two-dimensional (213) scalable cluster states. Positivity of partial transpose criteria is used to predict whether the final state is distillable or not. A critical value on the error tolerance in constructing cluster states is determined, which could be used as a test-bed for successful construction of scalable 2D cluster states. Furthermore, our quantitative analysis would also be helpful to find optimal approach to suppress the noise accumulation. 相似文献
997.
998.
利用CCSD(T)方法和系列相关一致基cc-pVXZ及aug-cc-pVXZ(X=D,T,Q,5)对SH和SD分子的基态平衡几何,谐振频率和离解能进行了优化计算.利用优选出的CCSD(T)/aug-cc-pV5Z方法对SH和SD的基态进行单点能计算,并将计算结果拟合成了Murrell-Sorbie函数.利用得到的解析势能函数,计算了SH和SD的其余3个光谱常数(ω_ex_e,α_e和B_c),结果表明:除SD的ω_ex_e值外,其余结果均与实验值符合得相当好,但计算得出的ω_ex_e值与推导出的值25.134 cm~(-1)符合得很好. 相似文献
999.
利用第三代电子动量谱仪研究了苯甲醇(C_6H_5CH_2OH)分子的最高占据轨道(HOMO)和次最高占据轨道(N-HOMO)电子动量谱,给出了外价轨道的电离能谱信息.实验在非共面对称几何条件下完成,入射电子的能量为2400 eV加结合能.通过密度泛函方法计算得到了苯甲醇分子最高和次最高占据轨道的动量谱,理论与实验结果符合较好. 相似文献
1000.
以硝酸钴(Co(NO3)2·6H2O)、硝酸铁(Fe(NO3)3·6H2O)和硫脲为原料,在同一混合溶剂(乙二醇和水)中通过控制两种溶剂的比例(1∶2; 4∶1),利用溶剂热法在180 ℃分别恒温制备了硫化钴(CoS1.097)和硫化铁(Fe3S4)两种纳米晶.用X-射线衍射(XRD)、透射电镜(TEM)对样品组成、粒径和表面形貌进行了表征,荧光光谱对其荧光性质进行了测量.结果表明,所得样品分别为六方相的CoS1.097和立方相的Fe3S4纳米粉末.在此基础上,对影响两种纳米晶形成的主要因素进行了初步的分析和讨论. 相似文献