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121.
考察了化学位移各向异性对半整数自旋四极核2D NMR章动的影响.用数值方法对2D NMR章动实验的演化期的Hamiltonian矩阵进行对角化,然后用帐篷法进行粉末平均,获得了自旋为I=3/2、5/2、7/2和9/2的四极核在不同化学位移各向异性下的2D NMR章动谱.实验结果与理论计算符合较好. 相似文献
122.
In this paper, we propose a distributed secure delegated quantum computation protocol, by which an almost classical client can delegate a -qubit quantum circuit to d quantum servers, where each server is equipped with a -qubit register that is used to process only k qubits of the delegated quantum circuit. None of servers can learn any information about the input and output of the computation. The only requirement for the client is that he or she has ability to prepare four possible qubits in the state of , where . The only requirement for servers is that each pair of them share some entangled states as ancillary qubits. Instead of assuming that all servers are interconnected directly by quantum channels, we introduce a third party in our protocol that is designed to distribute the entangled states between those servers. This would simplify the quantum network because the servers do not need to share a quantum channel. In the end, we show that our protocol can guarantee unconditional security of the computation under the situation where all servers, including the third party, are honest-but-curious and allowed to cooperate with each other. 相似文献
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126.
Renlong Zhou Xiaoshuang Chen Bingju Zhou Xiaojuan Liu Hui Deng Zhibin Deng Guozheng Nie Lingxi Wu Yongyi Gao 《Solid State Communications》2012,152(13):1186-1190
The coupled-nanowire plasmatic resonances and very strong negative electromagnetic force between the double-layer metallic nanowire arrays is investigated theoretically. The negative electromagnetic force indicates attractive interaction between the metallic nanowires with the air-gap cavity local resonance effect. Plasmon resonances lead to extremely large localized ?eld, thereby resulting in large mutual coupling forces between the double-layer metallic nanowire arrays. The light coupling into metallic microcavity can stimulate collective electron oscillations of plasmatic resonance, and cause the contraction of the negative pressure in metallic cavity wall. The electromagnetic field of the plasmatic resonance mode is mainly localized inside the air-gap region between the two wires. 相似文献
127.
By the density matrix renormalization group method, the phase diagram of the frustrated spin-1/2 ladder with the next nearest intrachain and ferromagnetic interchain couplings is obtained. According to our results, the two-rung entanglement is shown to be more sensitive than order parameters for determining phase boundary in such a frustrated spin ladder model. Furthermore, the additional next nearest intrachain coupling is found to enhance the intermediate columnar dimerized phase evidently. 相似文献
128.
Based on the exact solutions of the (3 + 1)-dimensional ((3 + 1)D) generalized nonlinear Schrödinger equation (GNLSE), we analyze the spatiotemporal propagation characteristics by intensity moments when a laser propagates in an inhomogeneous nonlinear medium. The different order intensity moment can describe the characteristics of a laser, and in the paper, the beam width (BW), the pulse width (PW), the skewness and the kurtosis parameter are calculated. The spatiotemporal propagation stability of the exact solutions is analyzed in detail by the second-order intensity moment. We find that when the diffraction and dispersion coefficients are the identical distributed functions, the BW and PW of the exact solutions are constants or vary periodically during nonlinear propagation. So, the spatiotemporal propagation of the exact solutions is stable. When the diffraction and dispersion coefficients are other coefficients, the BW and PW of the exact solutions vary irregularly due to the effect of a chirp. Thus the spatiotemporal propagation of the exact solutions is unstable. The results are helpful to the extendable investigation of nonlinear propagation and control of a laser pulse. 相似文献
129.
Monte Carlo study of the universal area distribution of clusters in the honeycomb O(n) loop model 下载免费PDF全文
We investigate the area distribution of clusters (loops) in the honeycomb O(n) loop model by means of the worm algorithm with n = 0.5, 1, 1.5, and 2. At the critical point, the number of clusters, whose enclosed area is greater than A, is proportional to A-1 with a proportionality constant C. We confirm numerically that C is universal, and its value agrees well with the predictions based on the Coulomb gas method. 相似文献
130.
Huizhou Wu Xiangbo Yang Yan Tang Xiaopeng Tang Dongmei Deng Hongzhan Liu Zhongchao Wei 《Annalen der Physik》2019,531(9)
A PT‐symmetric periodic structure with two‐material waveguide networks is constructed. In this study, how changing the number of cells affects the transmission properties is investigated. The results show that the PT‐unbroken (broken) region of the system is only determined by the cell structure, regardless of the number of unit cells. This means that any system has the same exceptional points (EPs), regardless of the number of cells and as long as the cell structure is consistent. In addition, it is confirmed that the coherent perfect absorbers and lasers (CPA lasers) occur in our model. The transfer matrix method is used to derive a sufficient condition for achieving the CPA laser point. A simple, effective formula for predicting the CPA laser state in an N unit cell system is derived. 相似文献