Controlled Remote State Preparation of an Arbitrary Two-Qubit State by Using Two Sets of Four-Qubit GHZ States

Recently, Huang and Zhao (Int. J. Theor. Phys. 56, 678, 2017) proposed a new scheme for controlled remote state preparation of an arbitrary two-qubit state by using two sets of three-qubit GHZ states as the quantum channel. In the scheme, Alice and Bob choose four different kinds of two-qubit projective measurement bases to measure their local qubits, respectively. We demonstrate that two sets of four-qubit GHZ states can be used to realize the deterministic controlled remote state preparation of an arbitrary two-qubit state by performing only two-qubit projective measurements.     

FM信号单音干扰效果评估方法

FM信号受单音干扰时,有时无法获取干扰信号信息,但易获取输入信号和输出信号信息。提出将均方误差公式进行改进,并与干信比这一指标相关联,间接对FM信号进行单音干扰效果评估的方法。首先,建立了FM信号仿真模型,分析了不同信噪比下FM解调信号的波形失真情况;其次,分析了FM调制信号受到单音干扰时,在不同干信比下FM解调信号的波形失真情况;然后,用均方误差公式来表示模拟信号失真度,分析其与干信比的变化曲线,并对均方误差公式进行改进,仿真研究后得到新的评估指标;最后,分析了新评估指标与干信比和占空比的关系。     

掺杂红外染料聚叠氮缩水甘油醚工质激光烧蚀推进性能优化探索

选择含能聚合物聚叠氮缩水甘油醚(GAP)作为激光烧蚀微推力器的工质,分析了红外染料掺杂对激光烧蚀GAP工质推进性能的影响.通过对比掺杂红外染料GAP在不同激光功率密度、掺杂浓度、靶材厚度和激光烧蚀模式下的推进性能数据和烧蚀羽流,初步探索了掺杂红外染料GAP工质的推进性能优化方式.实验结果表明:透射式激光烧蚀模式下,激光能量的指数衰减特性和掺杂红外染料GAP的强黏性使得烧蚀羽流中易存在未充分烧蚀的工质; GAP的推进性能受红外染料掺杂浓度和靶材厚度的综合影响,当靶材厚度与激光吸收深度接近时,靶材充分吸收激光能量使中心烧蚀区达到化学能释放的温度阈值,同时沿激光传播方向未充分烧蚀的质量最少,此时推进性能达到最优值.反射式下掺杂红外染料的聚合物的激光烧蚀过程遵循"先吸收激光能量先喷射"的规律,工质分解充分,推进性能优于透射式.     

分散有ZnS:Mn2+纳米超微粒的有机薄膜的制备和光学性质

近年来,半导体超微粒的合成及光物理性质研究已成为活跃的领域.由于量子尺寸效应引起的量子点能级结构的变化及其光学性质已经作了大量研究[1-4].1993年,Bhar-gava首次报导了化学反应合成的ZnS Mn超微粒的光学性质[5],掺杂半导体纳米材料的出现,为纳米科学的研究开辟了新的领域.     

纳米混合分子聚集体材料中弗兰克尔激子迁移的相位弛豫

在有机染料ＰＩＣ－１中引入其衍生物ａｚａＰＩＣ－Ｉ形成能量势垒，改变在混合分子聚集体中ＰＩＣ－Ｉ的Ｊ－聚集体的实体长度。用双调制外差检测的累积光子回波技术研究了相干弗兰克尔激子失相过程。观测到激子失相时间Ｔ２随ａｚａＰＩＣ－１克分子数的增大从６０ｐｓ变为２２４ｐｓ。     

Determine locking range of coherently combined fiber lasers joined by fiber couplers

When the wavelength difference of two fiber lasers, sharing a common reflection mirror with the aid of an optical coupler, is tuned to fall into a certain range, the array lasers can be locked to generate coherent radiation with a wavelength somewhere between the two constituent field wavelengths. Based on the fact that the laser should oscillate at the wavelength with the lowest losses and the band widths of the reflection curves of the laser tuning elements are finite, the locking range of the laser array has been quantified. For the tuning element (i.e., fiber gratings) selected in this work, the calculations show that the locking range is mainly dependent on the coupling coefficients of the gratings which ever is smaller.     

Analysis of planar waveguides with index discontinuity or index slope discontinuity

In this paper, we propose a novel analytic transfer matrix method (ATMM) to the analysis of planar waveguides with index discontinuity or index slope discontinuity, for the cases when the conventional WKB method is no longer valid. We also analyze the physical insight of the approximations in WKB theory, and according to our research, the phase shift at the turning point is not /2, but exactly . Test calculations are done for an index profile with a known solution and the comparison shows that our method gives extremely accurate propagation constant.     

1H NMR Studies on the Methylation,Protonation, and Hydration Sites in Some Benzo[b]Naphthyridines (Azaacridines)

Abstract

The 300.13 MHz ¹H NMR spectra of the methylated and protonated 6(9)-methylbenzo[b][1,x] naphthyridines (x=5, 6, 7, 8) (5-methylazaacridines) were collected at 298 K in deuterated dimethyl sulfoxide and chloroform, respectively. The methylation and protonation sites were assigned by comparisons of these data with those of the free bases. The results were compared with similar data for related heterocycles and showed that both methylation and protonation occur at the nitrogen in the outer pyrido ring in all four series.

The hydration site in some 2-and 3-azaacridines was determined by specific line broadening in their ¹H NMR spectra to be the same nitrogen as that involved in methylation and protonation. Variable temperature ¹H NMR demonstrated that the specific line broadening results from some changes of ¹⁴N quadrupolar relaxation produced by the slow chemical exchange between unhydrated and hydrated species. Deuterium exchange experiments indicated that the direct spin-spin interaction of a water proton and the protons alpha to the hydrated nitrogen may also have some contribution.     

Stress evolution and lattice distortion induced by thickness variation and lattice misfit in La0.67Sr0.33MnO3−δ films

La_0.67Sr_0.33MnO_3?δ thin films with different thicknesses are prepared in order to investigate the structural variation induced by film thickness and lattice misfit. The X-ray diffraction results show the in-built stress evolution from a full strained thin layer (～10 nm) to a completely relaxed thick layer (～150 nm), which can be well explained by the Poisson effect. Raman spectroscopy measurements reveal the complicated correlation between the Jahn–Teller (JT) distortion and film thickness. Important octahedron modes reflecting JT distortion are completely caused by the relaxed layer. It is observed that broad JT bands are formed in the films with large thickness of the relaxed layer and the residual stress in the layer leads to an obvious blue shift. In contrast, for films with the thin relaxed layer, JT modes are present as a sharper structure and move to low frequency, indicating towards a much better oxygen stoichiometry.     

Mobile Rayleigh Doppler wind lidar based on double-edge technique

<正>We describe a mobile molecular Doppler wind lidar(DWL) based on double-edge technique for wind measurement of altitudes ranging from 10 to 40 km.A triple Fabry-Perot etalon is employed as a frequency discriminator to determine the Doppler shift proportional to the wind velocity.The lidar operates at 355 nm with a 45-cm-aperture telescope and a matching azimuth-over-elevation scanner that provides full hemispherical pointing.To guarantee wind accuracy,a single servo loop is used to monitor the outgoing laser frequency to remove inaccuracies due to the frequency drift of the laser or the etalon.The standard deviation of the outgoing laser frequency drift is 6.18 MHz and the corresponding velocity error is 1.11 m/s.The wind profiles measured by the DWL are in good agreement with the results of the wind profile radar(WPR).Evaluation is achieved by comparing at altitudes from 2 to 8 km.The relative error of horizontal wind speed is from 0.8 to 1.8 m/s in the compared ranges.The wind accuracy is less than 6 m/s at 40 km and 3 m/s at 10 km.