bluuebunny/crossref_metadata_2025 huggingface dataset:
The waveguide effect of hard X-ray photon sieves
Authors: Xie Chang-Qing  , Zhu Xiao-Li  , Jia Jia  ,   中国科学院微电子研究所，北京  100029
Published: December 2020

In this work,the waveguide effect inside the high high-aspect-ratio metal structure of hard X-ray photon sieves is studied based on fast fourier transform beam propagation method （FFT-BPM）. After the physical boundary condition immediately downstream of hard X-ray photon sieves is determined by FFT-BPM, the angular spectrum method is used to calculate the point spread function，and the absorber thickness impact on the focusing performance is analyzed. The results show that the waveguide effect can suppress the emergence of the high order diffraction of hard X-ray photon sieves to some extent,thus improve its focusing performance.Under the same feature size conditions, the spatial resolution of hard X-ray photon sieves is better than that of Fresnel zone plates,with the drawback of lower diffraction efficiency.With the absorber thickness increasing, both the focusing performance and diffraction efficiency of photon sieves will improve, but the difficulty of the corresponding nanofabrication process will also increase.
The effect of concentrated light intensity on output performance of solar cell arrays
Authors: Xu Yong-Feng  , Li Ming  , Wang Liu-Ling  , Lin Wen-Xian  , Zhang Xing-Hua  , Xiang Ming  , Wang Yun-Feng  , Wei Sheng-Xian  ,   (1)云南师范大学可再生能源材料先进技术与制备教育部重点实验室,昆明  650092; (2)云南师范大学可再生能源材料先进技术与制备教育部重点实验室,昆明  650092；云南师范大学物理与电子信息学院,昆明  650092; (3)云南师范大学物理与电子信息学院,昆明  650092
Published: December 2020

Detailed analysis on the output characteristic and power influence factors of crystal silicon solar cell arrays and GaAs cell arrays have been done based on trough concentrating photovoltaic/thermal system. The results show that under concentrated light intensity, the output performance of GaAs cell array is better than crystal silicon solar cell arrays. Band-gap of solar cell arrays narrows and short circuit current increases very much in concentrated light intensity, which are good for output power. But open circuit voltage of cells drops a little for high recombination rate in depletion region produced by high light intensity, which has a restrictive effect to output power. At the same time the series resistance of cell arrays increases and working temperature of cell arrays rises which are brought about by high concentrated light intensity. In high concentrated light intensity, series resistance of cell arrays hugely affect the output power. When series resistance increases from 0 Ω to 1 Ω, the out put power of four cell arrays respectively drop by 6778%, 7493%, 7730% and 5801%.
Analysis of the variability periodicities of quasar 3C345
Authors: Dong Fu-Tong  , Zhang Xiong  ,   云南师范大学物理与电子信息学院，昆明  650092
Published: December 2020

This paper has collected all available optical B magnitudes of quasar 3C345 of more than 100 years, and acquired it's long-term light curve. We make a muti-time scale analysis to it's B band data with the wavelet analysis method, and get the wavelet transform coefficient plots to demonstrate the explosion process of the optical B band of 3C345. From the analysis, we have found that threr exist approximate periods of 450 d, 780 d, 1830 d and 3540 d. The inverse wavelet transform shows the light curve variability of 3C345 on different time scales, so we can predict it's possible explosion time is the year of 2010.
Analysis of chaos and circuit implementation of a permanent magnet synchronous motor
Authors: Xue Wei  , Guo Yan-Ling  , Chen Zeng-Qiang  ,   (1)南开大学自动化系，天津  300071; (2)天津科技大学自动化系，天津  300222
Published: December 2020

The permanent magnet synchronous motor, which is a nonlinear dynamic system, can exhibit a variety of chaotic or limit cycle phenomenon under some choices of system parameters and external inputs, and its chaotic characteristics are more prominent. Based on the mathematical model of a permanent magnet synchronous motor, its nonlinear characteristics are analysed with respect to the bifurcation diagram, Lyapunov exponent map and the nature of its equilibrium point in this paper, and the results in well demonstrated by numerical simulations. Finally, an analog electronic circuit is designed to implement the mathematical model of a permanent magnet synchronous motor, and the experimental results of the system well agreed with the simulation results.
Numerical solution of the three-dimensional time-dependent Schr?dinger equation and its application
Authors: Zeng Si-Liang  , Zou Shi-Yang  , Wang Jian-Guo  , Yan Jun  ,   (1)北京应用物理与计算数学研究所，北京  100088; (2)北京应用物理与计算数学研究所，北京  100088；北京大学应用物理与技术研究中心，北京  100871
Published: December 2020

We present an accurate and effective pseudospectral method for solving the three-dimensional time-dependent Schrdinger equation involving the Coulomb potential. In this method, the Hamiltonian is evaluated by exploiting the two representations of the wave function. One is a grid representation, in which the angular dependence of the wave function is expanded in a two-dimensional Gauss-Legendre-Fourier grid in the coordinate space of polar and azimuthal angles. The radial coordinate is discretized using a discrete variable representation constructed from the Coulomb wave function （CWDVR）. The other is a spectral representation, in which the wave function is expanded in a set of square integrable functions chosen as the eigenfunctions of a zero-order Hamiltonian. The time of propagation of the wave function is calculated using the well-known second-order split-operator method implemented through the transform between the grid and spectral representations. Calculations on the photo-absorption strength of hydrogen atom are presented to demonstrate the accuracy of present method in low energy limit by the time-dependent wave-packet propagation method. As another example, the present method is applied to multiphoton ionization of H atom. For a wide range of field parameters, ionization rates calculated using the present method are in excellent agreement with those from other accurate numerical calculations. The new algorithm will be found more efficient than the close coupled wave packet method using CWDVR and/or methods based on evenly spaced grids.
Molecule structure and analytical potential energy function for the ground state of MgB2
Authors: Ruan Wen  , Hu Qiang-Lin  , Xie An-Dong  , Yu Xiao-Guang  , Luo Wen-Lang  , Zhu Zheng-He  ,   (1)井冈山大学数理学院，吉安  343009; (2)井冈山大学数理学院，吉安  343009；四川大学原子与分子物理研究所，成都  610065; (3)四川大学原子与分子物理研究所，成都  610065
Published: December 2020

Ab initio methods and density functional theory B3LYP with QCISD/6-311++G** basis set have been used to calculate the equilibrium geometries and vibrational properties of the possible structures and electronic states of MgB2 molecule. The present computational results predict that the ground electronic state is the triplet state 3B1 of C2v （B—Mg—B） with equilibrium geometry Re=2.2977，αBMgB=41.5521° and the energy of the ground state 3B1 is -248.9645 a.u.. Similarly, the harmonic frequency has been calculated. Then, the analytic potential energy function of MgB2 molecule is derived by many-body expansion theory for the first time. The contours of the potential energy surface are constructed, which clearly reproduce the character of the accurate equilibrium structure and dissociation energy for MgB2 molecule. Furthermore, the molecular static reaction pathway is investigated based on this potential energy function.
Similarity of high-order cumulants for single molecule kinetics
Authors: Zheng Yu-Jun  , Zhang Zhao-Yu  , Zhang Xi-Zhong  ,   (1)济宁职业技术学院计算机工程系，济宁  272000; (2)青岛农业大学建筑工程学院，青岛  266109; (3)山东大学物理学院，济南  250100
Published: December 2020

In this paper, we study the similarity of high-order cumulants of single molecule kinetics based on the generating function approach developed recently. The high-order cumulants have their differences for the different models compared with single molecule kinetics although the generating functions of the models are of the maximum similarity.
Focusing characteristic of chromium atoms under elliptical standing wave
Authors: Zhang Wen-Tao  , Zhu Bao-Hua  , Xiong Xian-Ming  ,   桂林电子科技大学电子工程学院，桂林   541004
Published: December 2020

Direct-write atom lithography is a new technique in which resonant light is used to pattern an atomic beam and the nanostructures are formed when the atoms are deposited on the substrate. The characteristics of chromium atoms deposit on a substrateare are discussed. We simulated and analysed the characteristics of nanostructure under different laser power and on different y-plane. At the same time, the characteristics of nanostructure are analysed with respect to the effects of atomic beam divergence, the resulting full width at half maximum and contrast are shown under respective conditions.
Investigation of atom-optical properties of laser focused Cr atomic deposition
Authors: Lu Xiang-Dong  , Li Tong-Bao  , Ma Yan  , Wang Li-Dong  ,   (1)同济大学物理系，上海  200092; (2)同济大学物理系，上海  200092；桂林电子科技大学电子工程学院，桂林  541004
Published: December 2020

Gating structure of one dimensional Cr layer is experimentally obtained through the technology of laser focused atomic deposition. The periodicity of grating is （212.8±0.2） nm measured by atomic force microscope, which is just equal to half of the wavelength of laser standing-wave field. Then, based on the semiclassical model and numerical calculation of the Adams-Bashforth-Moulton algorithm, both Cr atom motion trajectories are simulated and the atom-optical properties are analyzed at the same experimental conditions. The results show that the analytical results agree well with the experimental results.
Density functional study of CO2 adsorption on Pu(100) surface
Authors: Meng Da-Qiao  , Luo Wen-Hua  , Li Gan  , Chen Hu-Chi  ,   表面物理与化学国家重点实验室，绵阳  621907
Published: December 2020

The adsorption of CO2 on Pu（100） surface has been studied with periodic slab model by revised Perdew-Burke-Ernzerh approximation within the framework of density functional theory. The optimized results of adsorption energies and geometrical structures show that the H-C4O4-type adsorption is optimum adsorption mode with adsorption energy of 1.48 eV. The atomic population and density of states analysis indicate that the interaction between Pu atom and CO2 molecule results mainly from strong electron transfer and weak overlap-hybridization between molecular orbital 2πμ of CO2 molecule and Pu5f, Pu6d and Pu7s orbitals of surface Pu atom. The calculated activation barrier and adsorption energy CO2→CO+O dissociative reaction are 0.66 and 2.65 eV, respectively, which indicates the dissociative adsorption of CO2 on Pu（100） surface is favorable under the certain heat activation condition. The comparison of O2，H2，CO and CO2 adsorption on Pu（100） surface indicates the adsorption strength follows the ordering: O2，CO，CO2，H2 and O2，CO2，CO，H2 at lower and higher temperature, respectively.
An improved shift operator finite-difference time-domain method based on digital signal processing technique for general dispersive medium
Authors: Zhang Yu-Qiang  , Ge De-Biao  ,   (1)西安电子科技大学物理系,西安  710071; (2)西安电子科技大学物理系,西安  710071；延安大学物理与电子信息学院，延安  716000
Published: December 2020

An improved shift operator finite-difference time-domain （SO-FDTD） method for general dispersive medium based on the implementation of infinite impulse response filter in digital signal processing technique is presented. Compared with the commonly used SO-FDTD, the storage variables in the improved SO-FDTD are reduced by 33% and computational efficiency is also increased. Finally, the generality and the feasibility of the presented scheme are validated by calculations of scattering by first order and second order dispersive objects.
Coherent transmission of terahertz wave through randomly packed subwavelength-sized aluminium particles
Authors: Chen Hua  , Wang Li  ,   (1)中国科学院物理研究所光物理实验室，北京  100190; (2)中国科学院物理研究所光物理实验室，北京  100190；东南大学物理系，南京  211189
Published: December 2020

We experimentally discovered that the efficient coupling of surface plasmon wave to free-space radiation beyond the interaction zone via random metallic particles. In the experiments of terahertz wave transmission through an ensemble of randomly packed aluminium particles with sub-wavelength sizes, we observed a strong dependence of the transmission on the lateral boundary conditions. Our results showed that the processes of terahertz wave propagating in the disk-shaped samples and reemitting to the free space were resulted from surface modes excitation, which is critically affected by lateral sizes of the particle ensembles.
Self-consistent field description of whispering-gallery mode in circular cavity
Authors: Qiu Shan-Liang  , Li Yong-Ping  ,   (1)中国科学技术大学物理系，合肥  230026; (2)中国科学技术大学物理系，合肥  230026；中国科学技术大学 中国科学院量子信息重点实验室，合肥  230026
Published: December 2020

On the base of introduction of circular cavity eigenfield and its reflection coefficient，the self-consistent field description of whispering-gallery mode （WGM） in circular cavity is discussed. Accroding to the self-consistency，the same eigenvalue equation as the one directly deduced from the Helmholtz equation determining WGM is obtained. Also based on the wave-ray correspondence of circular cavity eigenfield，the self-consistent ray description of WGM is discussed. The results of resonance wavenumbers and the Q-factors of WGMs deduced from the intuitive self-consistent picture of eigenray beam are well coincident with the ones obtained by directly solving the eigenvalue equation.
Effects of gain saturation in terahertz radiation based on difference frequency generation
Authors: Huang Nan  , Li Xue-Feng  , Liu Hong-Jun  , Xia Cai-Peng  ,   (1)西安邮电学院应用数理系，西安  710121; (2)中国科学院西安光学精密机械研究所瞬态光学与光子技术国家重点实验室，西安  710119; (3)中国科学院西安光学精密机械研究所瞬态光学与光子技术国家重点实验室，西安  710119；西安邮电学院应用数理系，西安  710121
Published: December 2020

Numerical studies of terahertz （THz） radiation based on difference frequency generation in GaSe crystal are reported. When the gain saturation is achieved at a wavelength of 227.5 μm，which corresponds to a crystal length of 26.3 mm，the peak output power for THz radiation reaches 945 W. As a result of crystal absorption，the gain saturation region of THz radiation is the unstable output region，which is in front of the stable output region; and the stability of THz radiation is determined by the stability of pump. The peak output power for THz radiation reaches 735 W at the wavelength of 227.5 μm and at the corresponding crystal length of 37.9 mm in stable region.
Analytical solution in the Ince-Gaussian form of the beam propagating in the strong nonlocal media
Authors: Zhang Xia-Ping  , Liu You-Wen  ,   (1)南京航空航天大学理学院，南京  210016; (2)南京航空航天大学理学院，南京  210016；南京晓庄学院物理系，南京  210017
Published: December 2020

Based on the Snyder-Mitchell model that describes the paraxial beam propagating in strongly nonlocal nonlinear media and by constituting the trial solution with modulating the Gaussian beam by Ince polynomials in elliptic coordinate，the close forms of Ince-Gaussian beams have been accessed. Depending on the power of the beam，the Ince-Gaussian beams can be either a soliton state when the input power is equal to the critical power or a breather state. The Ince-Gaussian beams constitute the exact and continuous transition modes between Hermite-Gaussian beams and Laguerre-Gaussian beams. The profiles of the breather at different propagating distance are numerically obtained and the transitions of a few Ince solitons are given.
Augmenting the mixing of size-type binary granular systems in a rotating horizontal drum
Authors: Zhao Yong-Zhi  , Zhang Xian-Qi  , Liu Yan-Lei  , Zheng Jin-Yang  ,   (1)浙江大学化工机械研究所,杭州  310027; (2)浙江大学医学院附属第二医院,杭州  310009
Published: December 2020

Cross shaped baffles are set in the horizontal drum to augment mixing of the size-type binary particles, and the discrete element method was employed to study the mixing of the size-type binary granular systems in the rotating horizontal drums with different sized cross shaped baffles. The influences of the baffle and the size of the baffle on the mixing were discussed. The mechanisms of the augmenting of mixing of the baffles were discussed in this paper. The simulation results show that the convection, the diffusion and the segregation controlled the mixing and demixing of the binary granular systems in the rotating horizontal drum without baffle. When the baffle was set in the drum, only the convection and the diffusion operated, and the segregation of the binary particles were suppressed, because the cross shaped baffles can break the free-surface flow in the drum and the segregation of the binary particles in the free-surface flow can not occur, and the mixing can be enhanced. An optimum size of the baffle exists for the augmenting mixing of the size-type binary granular systems in the drum with baffles. The oversized and undersized baffles are unfavorable for the mixing of binary particles in the drum.
Enhancing compressive strength of electrorheological fluid by patterning the electrode
Authors: Zhang Min-Liang  , Tian Yu  , Jiang Ji-Le  , Meng Yong-Gang  , Wen Shi-Zhu  ,   清华大学摩擦学国家重点实验室，北京  100084
Published: December 2020

Slip at the interface of solidified electrorheological （ER） fluid and electrodes is harmful for ER applications. Compression tests using four kinds of electrodes, namely the smooth, hole array patterned by laser pulse, nylon net covered, and acid etched column patterned electrodes, have been done, respectively. Results show that laser patterned and nylon net covered electrodes significantly enhanced the compressive stress of the ER fluid. The enhancement is ascribed to the increase of local electric field near electrodes after patterning, which increased the interfacial strength between ER fluid and electrodes, and effectively suppressed the slip of solidified ER fluid from electrode. The tests of current density during compression and the finite element analysis of the electric field distribution of patterned electrodes supported this slip suppression effect. The results raised a fundamental question of what is the real strength of ER fluids, since the slip of highly solidified ER fluid are usually not considered during various tests. This investigation also shows that patterning electrodes is a good way to improve mechanical performances of ER fluids.
Three-dimensional numerical simulation of the edger and corner metal’s flow on edging rolling on roughing of hot continuous rolling process
Authors: Wang Xiao-Nan  , Di Hong-Shuang  , Liang Bing-Jie  , Xia Xiao-Ming  ,   (1)东北大学轧制技术及连轧自动化国家重点实验室,沈阳  110004; (2)东北大学轧制技术及连轧自动化国家重点实验室,沈阳  110004；上海梅山钢铁股份有限公司热轧板厂，上海  210039
Published: December 2020

Based on the seam-defect appearing on the plate edge of rough-rolling medium billet in the Meishan Iron and Steel Companys hot-rolling units, the five-pass reversible vertical-horizontal rolling of different vertical roll shapes process is simulated numerically. The results show that groove vertical rolls rolling can inhibit double bulging deformation better. On the same rolling process conditions, the value of side tumbling on groove vertical rolling is larger than that on flat vertical rolling, and the value of side tumbling increases with the groove fillet radius increasing. During the rolling process, that the metal at low temperature, high strain and high stress cumulates on the edge of the workpiece may bring the seam-defect along the length of the workpiece. The edge interlayers could be avoided by reasonably designing the vertical roll shape and optimizing the vertical rolls screw system, thereby reducing or avoiding the occurrence of seam-defects.
Velocity gradient in Kelvin-Helmholtz instability for supersonic fluid
Authors: Wang Li-Feng  , Teng Ai-Ping  , Ye Wen-Hua  , Fan Zheng-Feng  , Tao Ye-Sheng  , Lin Chuan-Dong  , Li Ying-Jun  ,   (1)北京大学应用物理与技术研究中心，北京  100871；北京应用物理与计算数学研究所，北京  100088; (2)北京应用物理与计算数学研究所，北京  100088; (3)中国矿业大学（北京）力学与建筑工程学院和理学院，北京  100083; (4)中国矿业大学（北京）力学与建筑工程学院和理学院，北京  100083；北京应用物理与计算数学研究所，北京  100088
Published: December 2020

Two-dimensional numerical calculations using weighted essentially non-oscillatory schemes （WENO） scheme were performed to study velocity gradient in the Kelvin-Helmholtz （KH） instability for supersonic fluid. It is found that the velocity gradient has a stabilization effect on the KH instability for supersonic fluid, and the linear growth rate empirical formula with velocity gradient stabilization effect is deduced. The empirical formula with velocity gradient stabilization effect agrees well will the simulation results. The sharp density contour is obtained, which indicates that the WENO finite difference scheme has good capturing ability in interface deformation. The evolution of KH vortex is influenced by the velocity gradient. When the density gradient is fixed, it is found that the larger the velocity gradient the smaller the transverse scale of the KH vortex.
Investigation of scaling laws for radiation temperature with shock wave velocity in Al
Authors: Jiang Shao-En  , Li San-Wei  ,   中国工程物理研究院激光聚变研究中心，绵阳  621900
Published: December 2020

The scaling laws of the radiation temperature with shock wave velocity in Al were simulated and investigated with one-dimensional radiation hydrodynamic program Hyades. The simulation results indicated that the formula Tr=0.0126D0.63 could be valid for the radiation temperature generated by the shaped pulse of lasers such as PS22 and PS26 profile on Nova facilities and Shenguang Ⅲ Prototype （SGⅢ Prot）, but was not suited for the radiation temperature by laser pulse with the Gaussian and trapezoid profiles, for which the scaling should be given by the modified formula，which well agrees with similarity solution. Additionally, the minimum thickness sustaining stable shock wave velocity driven by the radiation temperature with the shaped profile on SGⅢ Prot was also obtained by using the Hyades code. Finally, The experiments of shock wave driven radiation were made on Shenguang Ⅱ laser facilities. The radiation temperature Tr calculated from the modified scaling relation well agreed with the Tr measured by the soft X-ray spectrometer. The experimental results also showed the reliability of the modified formula.
Y elastic constants of polycrystalline materials with hexagonal system structure
Authors: Lin Zheng  , Liu Min  ,   (1)北京惠利尔知识产权信息咨询有限责任公司，北京  100028; (2)中国航空学会，北京  100012
Published: December 2020

In this paper, the physical parameters Y elastic constants mewly proposed in our previous paper are applied to polycrystalline materials with hexagonal structure to deduce Y elastic constants thereof and to compare with the x-ray elastic constants of polycrystalline materials of hexagonal structure through calculation of examples. Though the expressions of mechanical elastic constants of polycrystalline materials deduced from the application of Y elastic constants are different from the conclusions of Kneer, the calculaled results for concrete materials are in full compliance.
Numerical simulation of space charge packet behavior in low-density polyethylene under direct current voltage
Authors: Xia Jun-Feng  , Zhang Ye-Wen  , Zheng Fei-Hu  , Lei Qing-Quan  ,   (1)哈尔滨理工大学 电气与电子工程学院，哈尔滨  150080; (2)同济大学波耳固体物理研究所，上海  200092
Published: December 2020

Packet-like space charge behavior is a kind of special transport behavior of space charge in polyethylene. It has been demonstrated that many factors, such as the intensity of applied field, temperature and material have great influence on the formation and migration of space charge packets. This would cause much difficulty in understaning the general mechanism of the phenomenon. In this paper, on the basis of analysis of charge injection and migration, the interaction between the charge and charge trap and the influence of electric field on charge trap level, a model is proposed to simulate the packet-like space charge behavior. We suppose thar there exists a negative differential relationship for the charge velocity against the electric field when the electric ficld exceeds a threshold value. By considering the negative differential relationship, we simulated various kinds of packet-like charge behaviors and the results of numerical simulation show a good agreement with the experimental results issued by different research groups.
Electronic transport properties of the multilayer structure double spin-filter tunnel junction
Authors: Jin Lian  , Zhu Lin  , Li Ling  , Xie Zheng-Wei  ,   (1)乐山师范学院物理与电子信息科学系，乐山  614004; (2)四川师范大学物理与电子工程学院，成都  610066
Published: December 2020

Based on the transfer matrix method and the quantum coherent transport theory of Mireles and Kirczenow, the effects of the Rashba spin-orbit coupling and the spin-filter on the electronic transport properties in the NM/FS1/I/FS2/NM（NM represents the nonmagnetic metal layer, I represents the nonmagnetic insulator layer, and FS represents the magnetic semiconductor layer）double spin-filter tunnel junction are investigated. The influence of thickness of insulator layer and magnetic semiconductor layer on the tunnel magnetoresistance （TMR） and conductance are studied for different Rashba spin-orbit coupling strength and the different angle θ between the two magnetic moments of the left and right magnetic semiconductor layer. The results indicate that: in the presence of the spin-filter effect and the Rashba spin-orbit coupling interaction in the magnetic semiconductor layer, large TMR can be obtained in this double spin-filter junction. With the strength of Rashba spin-orbit coupling increasing, the tunnel magnetoresistance and conductance exhibit rapidly oscillating behavior and the oscillation period decreases gradually.
Synthesis of silicon oxide nanocluster and C-Si-O nanospheres morphology and photoluminscence Fourier transform infrared spectroscopy study
Authors: Zheng Li-Ren  , Huang Bai-Biao  , Wei Ji-Yong  ,   (1)山东大学晶体材料国家重点实验室，济南  250100; (2)泰山学院物理与电子科学系，泰安  271021
Published: December 2020

Silicon oxide nanocluster and C-Si-O nanospheres are fabricated by the chemical vapor deposition method at 1100℃，in flowing N2/H2 atmosphere using the ferrcene and the silicon oil （201） as the raw material and the catalyzer, respcetively. The silicon oxide nanowires are uniform with diameter of 5—40 nm and length up to hundreds of nanometer. The diameter of the C-Si-O solid-nanospheres is 100—300 nm. SEM，TEM，EDS，FTIR and PL were used to characterize the microstructure，composition and optical propertics of the nanocluster and the C-Si-O nanospheres. Energy dispersive X-ray spectrum analysis reveals that the C-Si-O nanospheres consist of C，Si and O elements in an atomic ratio of approximately 1.13∶1∶2.35. The nanoclusters show IR absorption peaks at 474，802 and 1100 cm-1. The PL peak of the nanoclusters is at 440 nm. It is very curious that the PL of the C-Si-O solid-nanospheres possesses the red，green and blue——trichromic luminescent peeks.
Emission properties of impregnated cathode with nanoparticle films
Authors: Liu Yan-Wen  , Tian Hong  , Han Yong  , Zhu Hong  , Li Yu-Tao  , Xu Zhen-Ying  , Meng Ming-Feng  , Yi Hong-Xia  , Lu Yu-Xin  , Zhang Hong-Lai  , Liu Pu-Kun  ,   中国科学院电子学研究所，北京  100190
Published: December 2020

The Ir nano particle thin film was grown by dcrect current magnetron sputtering at room temperature. Microstructure of thin films grown at different sputtering pressures were measured by scanning electron microscopy. The results show that the particle size of the films depends on the deposition rate in the nucleation stage of Ir films and the deposition rate can be well controlled by sputtering pressure. A new kind of cathodes are fabricated from 25% porous tungsten impregnated with 6∶1∶2-type barium calcium aluminate and coated with the nano particulate Ir thin film. The coating processes produces a film thickness of 200—500 nm and the cathodes are fired in hydrogen atmosphere for ten minutes at 1200℃ to further improve the coating microstructure. The cathodes have been studied with thermal electron microscope by which the electron-optical picture of a thermal emission cathode could be obtained. Time of flight mass spectrometer （ToFMS） has been used in a study of evaporation from impregnated cathodes. The chemical composition of evaporation of various impregnated cathodes have been measured by ToFMS. The variation of ion current of evaporants from S-type cathode and M-type cathode （coated with iridium） and n-type cathode （coated with iridium nano-particle thin film） with temperature and time have been studied and discussed. Emission current characteristics have been measured as a function of voltage and temperature.
Approximate solution of sea-air oscillator for El Ni?o-southern oscillation model
Authors: Mo Jia-Qi  , Lin Yi-Hua  , Lin Wan-Tao  ,   (1)ALSG, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029 China; (2)Department of Mathematics, Anhui Normal University, Wuhu 241000, China, Division of Computational Science, E-Institutes of Shanghai Universities, at SJTU, Shanghai 200240, China
Published: December 2020

A class of time delayed coupled system of the El Niñ,o-southern oscillation (ENSO) model is considered. By using the homotopic mapping method, the approximate expansion of the solution for the ENSO model is obtained and the asymptotic behavior of solution of corresponding problem is studied.
Virus spreading on complex networks with imperfect immunization
Authors: Wang Ya-Qi  , Jiang Guo-Ping  ,   (1)Center for Control & Intelligence Technology, Nanjing University of Posts and Telecommunications, Nanjing 210003, China; (2)Center for Control & Intelligence Technology, Nanjing University of Posts and Telecommunications, Nanjing 210003, China, College of Automation, Nanjing University of Posts and Telecommunications, Nanjing 210003, China
Published: December 2020

The imperfect immunization includes immune failure and immune invalidity on complex networks. In this paper, based on mean-field theory, we propose a new susceptible-infected-removed model to study epidemic spreading in networks with both immune failure and immune invalidity. Theoretical analysis shows that the immune failure and immune invalidity can significantly reduce the epidemic threshold and enhance the epidemic prevalence in the networks. According to the relationships between epidemic threshold, immune density of nodes, immune success rate and immune invalid rate, some suggestions on how to effectively control the propagation of epidemics are presented. Numerical simulations have confirmed the theoretical results.
Direct perturbation method applied to three-dimensional nonlinear Schr?dinger equation
Authors: Cheng Xue-Ping  , Lin Ji  , Han Ping  ,   (1)Physics, Mathematics and Information College of Zhejiang Ocean University, Zhoushan 316004, China; (2)Physics, Mathematics and Information Engineering College of Zhejiang Normal University,Jinhua 321004, China
Published: December 2020

By applying the direct perturbation method to the 3-dimensional nonlinear Schrö,dinger equation with perturbation, we obtain its asymptotical solutions, which contain not only the zero-order solutions, but also the first-order corrections. Through these solutions, the effect of perturbation on the soliton is analyzed as well.
Abundant interaction solutions of the mKdV-sine-Gordon equation
Authors: Lü Da-Zhao  , Cui Yan-Ying  , Liu Chang-He  , Zhang Yan  ,   (1)Department of Basic Science, Gengdan Institute of Beijing University of Technology, Beijing 101301, China; (2)School of Science, Beijing University of Civil Engineering and Architecture,Beijing 100044, China
Published: December 2020

In this paper, based on the forms and structures of Wronskian solutions of the mKdV-sine-Gordon equation, a Wronskian form expansion method is presented to find abundant interaction solutions of the mKdV-sine-Gordon equation. One characteristic of the method is that Wronskian entries don’t satisfy linear partial differential equations.
Controlling entanglement sudden birth and sudden death of two-atom X-states in Tavis-Cummings model
Authors: Shan Chuan-Jia  , Liu Ji-Bing  , Chen Tao  , Liu Tang-Kun  , Huang Yan-Xia  , Li Hong  ,   College of Physics and Electronic Science, Hubei Normal University, Huangshi 435002,China
Published: December 2020

In this paper, we investigate the entanglement dynamics of two entangled two-level atoms with initial X state and dipole-dipole coupling intensity in Tavis-Cummings model. The interesting phenomena of entanglement sudden death as well as sudden birth appear during the evolution process. We analyze in detail the effect of purity of initially entangled state of two atoms, the dipole-dipole coupling intensity between two atoms, and the field in the Fock state on the apparition time of entanglement sudden death and entanglement sudden birth. Furthermore, the conditions for the conversion of entanglement sudden death and entanglement sudden birth can be generalized when the initial entangled state is not pure. The results show that the above system parameters affect the concurrence, entanglement sudden birth and sudden death remarkably, the dipole-dipole coupling intensity affects amplitudes of the concurrence oscillation and leads time interval of the ESD to decrease. With the increasing of the purity, the time of entanglement sudden death and entanglement sudden birth will decrease, it is also notable that invariant and stable entanglement, which can be controlled by different initial states of the atoms, occurs for particular initial X state.
Properties of Wigner function of spin coherent states based on Schwinger Bose operator realization
Authors: Song Jun  , Fan Hong-Yi  ,   (1)Department of Material Science and Engineering, University of Science and Technology of China, Hefei 230026, China; (2)Department of Material Science and Engineering, University of Science and Technology of China, Hefei 230026, China, Department of Mathematics and Physics, West Anhui University, Liuan 237012, China
Published: December 2020

Based on the Schwinger Bose operator realization of angular momentum, we introduce the entangled state representation as well as the Wigner operator in such representation and then derive the Wigner quasiprobability function of spin coherent states. The properties of corresponding Wigner function in the phase space are discussed by numerical calculation. The results indicate that the spin coherent states based on Schwinger Bose operator realization actually show entanglement properties.
Exact solutions of the Schr?dinger equation for a ring-shaped noncentral potential
Authors: Zhang Min-Cang  , Huangfu Guo-Qing  ,   (1)College of Physics and Information Technology, Shaanxi Normal University, Xi’an 710062, China; (2)Department of Physics and Electronic Engineering, Weinan Teachers University, Weinan 714000, China
Published: December 2020

A new ring-shaped noncentral potential is proposed and the exact complete solutions of the Schrö,dinger equation with this potential are presented by the Nikiforov-Uvarov method.The effect of the angle-dependent part on the radial solutions and some particular cases of this potential are also discussed.
Recurrence spectra of Rydberg NO molecules in a strong magnetic field
Authors: Li Hong-Yun  , Lin Sheng-Lu  , Liu Wei  ,   (1)College of Physics and Electronics, Shandong Normal University, Ji’nan 250014, China; (2)Department of Information Engineering, Laiwu Vocational and Technical College, Laiwu 271100, China; (3)News Center, University of Jinan, Ji’nan 250022, China
Published: December 2020

Considering the influence of core rotation, we calculate the recurrence spectra of Rydberg NO molecules in the strong external magnetic field by using the molecular closed orbit theory and the multichannel quantum defect theory. The results indicate that the complicated recurrence spectra can be explained by the molecular closed orbit theory including the molecular core-scattering. Not only the elastic core-scattering effect arising from the intrachannel scattering, but also the inelastic core-scattering effect arising from the interchannel scattering is vital to the dynamical properties of the Rydberg molecule. Especially on the larger scaled action, the contribution of core-scattering is more crucial than that of the primary closed orbits and their repetition, and affects the dynamical properties of system to a large extent.
Single-particle coherence and pairwise entanglement in a two-component Bose-Einstein condensate impacted by the periodic impulses
Authors: Yan Dong  , Song Li-Jun  ,   (1)School of Science, Changchun University, Changchun 130022, China; (2)School of Science, Changchun University, Changchun 130022, China, College of Physics, Jilin University, Changchun 130022, China
Published: December 2020

The influence of the quantum chaos on the single-particle coherence and the pairwise entanglement is investigated in a two-component Bose-Einstein condensate impacted by periodic impulses. The results reveal that the single-particle coherence decays strongly when driven by chaos and keeps a lower degree of coherence. Simultaneously, there apears the maximal pairwise entanglement and it disappears after a short time. By using the properties of the single-particle coherence, we can measure directly the structure of the phase space in which the chaos exists, and this contributes to prevent the collapse of a Bose-Einstein condensate and control the chaotic behavior.
Subspace quantum process tomography via nuclear magnetic resonance
Authors: Yao Xi-Wei  , Zeng Bi-Rong  , Liu Qin  , Mu Xiao-Yang  , Lin Xing-Cheng  , Yang Chun  , Pan Jian  , Chen Zhong  ,   (1)Department of Materials Science and Engineering, Xiamen University, Xiamen 361005, China; (2)Department of Physics, Fujian Provincal Key Laboratory of Plasma and Magnetic Resonance, Xiamen University, Xiamen 361005, China
Published: December 2020

Experimental investigation of subspace quantum process tomography in three-spin system was implemented via nuclear magnetic resonance. A quantum process was characterized by measuring a complete set of input states and corresponding outputs. The method using ancillary qubit remarkably reduces the number of the initial input states. And the pulse sequences used in this paper have fewer J-coupling evolutions. The experiment time was shortened and quantum decoherence of the system was weakened efficiently.
Corrections to Hawking radiation from the black hole surrounded by quintessence
Authors: Gong Tian-Xi  , Wang Yong-Jiu  ,   (1)Institute of Physics, Hunan Normal University, Changsha 410081, China; (2)Institute of Physics, Hunan Normal University, Changsha 410081, China, School of Physics, Hunan University of Science and Technology, Xiangtan 411201, China
Published: December 2020

In this paper, using the Hamilton-Jacobi method beyond semiclassical approximation in black hole physics which was developed by Banerjee and Majhi, we compute the temperature and entropy of the black hole surrounded by quintessence and obtain the corrected temperature and entropy. In the corrected entropy, the area law involves logarithmic area correction together with the standard inverse power of area term.
Synchronization between fractional-order chaotic system and chaotic system of integer orders
Authors: Zhou Ping  , Kuang Fei  ,   Institute of Applied Physics, Chongqing University of Posts and Telecommunications, Chongqing 400065, China
Published: December 2020

Based on the idea of tracking control and the stability theory of linear fractional-order system, chaotic synchronization between fractional-order chaotic system and chaotic system of integer orders is proposed. A compensation controller and a feedback controller are given. Synchronization between the fractional-order Chen chaotic system and the Loren chaotic system of integer orders is used to illustrate the effectiveness of the proposed synchronization approach. Numerical and circuit simulations coincide with the theoretical analysis.
Synchronization of spatiotemporal chaos in large scale rich-club network
Authors: Lü Ling  , Zou Jia-Rui  , Yang Ming  , Meng Le  , Guo Li  , Chai Yuan  ,   College of Physics and Electronic Technology, Liaoning Normal University, Dalian 116029, China
Published: December 2020

The Plankton spatiotemporal chaos system is taken as network node and constructed as a rich-club network through nonlinear coupling. The synchronization of spatiotemporal chaos for the above network is investigated. The general selection rule of nonlinear coupling function connecting nodes in the rich-club network is presented. Furthermore, the condition to realize the network synchronization is analyzed theoretically based on Lyapunov stability theory. Finally, the synchronization effect of spatiotemporal chaos for the rich-club network is checked through artificial simulation. The results show that complete synchronization can be realized for all rich nodes in the rich-club network and all nodes in every subnetwork constructed in star-shape.
Network model with synchronously increasing nodes and edges based on Web 2.0
Authors: Xiong Fei  , Liu Yun  , Si Xia-Meng  , Ding Fei  ,   Key Laboratory of Communication and Information Systems-Beijing Jiaotong University, Beijing Municipal Commission of Education, Beijing 100044, China
Published: December 2020

We investigate the growing process and topological features of Web 2.0 networks. By analyzing the network’s degree distribution, average degree and time evolution of the node degree of an actual blog on portal website, we found these properties are different from those of the former scale-free network models. According to the growth characteristics of actual networks, we put forward a new type of network with synchronously increasing nodes and edges, including construction algorithms of randomly linking and connection between close neighbours. The simulation results show that the networks generated from our model have power-law degree distribution in case of absence of the preferential attachment process, and the clustering coefficient increases and the connectivity correlations are assortative.
Nanofocusing by phase delayed plasmonic nanostructures illuminated with a linearly polarized light
Authors: Song Wen-Tao  , Lin Feng  , Fang Zhe-Yu  , Zhu Xing  ,   (1)School of Physics, State Key Laboratory for Mesoscopic Physics, Peking University, Beijing 100871, China; (2)School of Physics, State Key Laboratory for Mesoscopic Physics, Peking University, Beijing 100871, China, National Center for Nanoscience and Nanotechnology, Beijing 100190, China
Published: December 2020

We report the near-field nanofocusing through two types of plasmonic nanostructures consisting of annular grooves and annular slit, respectively. The radius of one half of each circle is designed to be bigger than the other half by half wavelength of the surface plasmon polaritons. By illuminating the structures with linearly polarized light, one single tight focal spot was detected by the scanning near-field optical microscope. Compared with the method of using radially polarized light, this method does not need to keep the center of the illuminating light right on the center of the structure, hence is much easier to use. Furthermore, theoretical simulations based on the finite-difference time-domain method testified the experimental results.
Nano-resolution imaging of filopodia in HeLa cells
Authors: Liu Lei  , Yu Bin  , Niu Han-Ben  , Chen Dan-Ni  ,   (1)College of Optoelectronic Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China; (2)Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China, College of Optoelectronic Science and Engineering, Huazhong Universit
Published: December 2020

Nano-resolution imaging based on single molecule localization is simulated with Matlab. A sample consisted of several lines of molecules are simulated imaged. The results demonstrate that two lines of molecules separated by 20 nm can be resolved. Effect of pixel size on the localization accuracy is also discussed here. Nano-resolution imaging is realized on an IX71 inverted fluorescent microscope with the resolution (FWHM) of 48 nm. Nano-resolution images of filopodias are reconstructed, in which filopodias with diameter of 75 nm are resolved.
Structure and properties of ZrnPd clusters by density-functional theory
Authors: Jin Rong  , Chen Xiao-Hong  ,   School of Physics and Chemistry,Xihua University,Chengdu 610039,China
Published: December 2020

The geometries, stabilities and electronic properties of ZrnPd (n=1—13) clusters have been systematically investigated by using density functional theory B3LYP/LANL2DZ Method. The optimized geometries of the ZrnPd clusters have been considered, and the growth patterns of the ZrnPd clusters have been discussed. The results show that the isomers with Pd atom on the surface of ZrnPd cluster are more stable. On the basis of the optimized geometries, various energetic properties including the average binding energies, the second-order difference of energies, the gaps between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO), have been calculated for the most stable isomers of ZrnPd clusters. The investigation shows that the ZrnPd (n=7, 12) clusters have high stability and the ZrnPd clusters are more stable in chemical stability than the respective ZrnCo and ZrnFe clusters. Magnetic clusters with higher magnetic moment can be acquired by doping Pd atom to Zrn (n>5) clusters. Mulliken population analysis shows that there is a weak charge transfer from Zr atoms to Pd atom for ZrnPd clusters.
The system of loading hidden information in random spectrum of Fourier domain and incremental compensation
Authors: Wang Xiao-Lei  , Li Zhi-Lei  , Zhai Hong-Chen  , Wang Ming-Wei  ,   Institute of Modern Optics, Nankai University, Key Laboratory of Optoelectronic Information Science & Technology, Ministry of Education, Tianjin 300071, China
Published: December 2020

The system of loading hidden information in random spectrum of Fourier domain and incremental compensation, which is based on optical principle and can be used in optical image information hiding, is proposed in this paper. A typical method of loading hidden information to the system is also presented. The random spectrum of host image multiplied by random phase mask is obtained by Fourier transform, and the hidden information is embedded in the random spectrum. At the same time, the effects induced by the hidden information can be compensated for by the proposed system. When the carrier image embedded with hidden information is decrypted with incorrect key-random phase mask, the hidden information will spread in the Fourier frequency domain, thus it is impossible to retrieve the hidden information. In addition, even though the attackers know the presence of hidden information and even the hiding method, they still can not decrypt the hidden content without the key, and it is also difficult to removal the hidden information without destroying the carrier image. While in the decryption process, neither the original image nor the information related to the hidden code is necessary. The feasibility of proposed system is demonstrated by simulation experiment and the robustness to the Gauss noise as well as salt and pepper noise is also presented at the end of this paper.