bluuebunny/crossref_metadata_2025 huggingface dataset:
Chaos control and synchronization in electrical-optical bistable systems
Authors: Niu Yong-Di  , Ma Wen-Qiang  , Wang Rong  ,   吉林大学物理学院,长春  130023
Published: December 2020

Based on the characteristic of the electrical-optical bistable system under the condition of long delay, we propose a new scheme of realizing chaos control and synchronization. The results of numerical calculation show that by adjusting the driving intensity and the state of the driving system, not only the driven system can achieve stable control of different periodic states, but also the general chaos synchronization between the driving system and driven system can be realized. Using the maximal Lyapunov exponent （MCLE） as the criterion, the parameter range for realizing chaos synchronization is given.
p-moment stability of stochastic impulsive differential equations and impulsive synchronization of Lorenz system excited by parameter white-noise
Authors: Niu Yu-Jun  , Xu Wei  , Rong Hai-Wu  , Wang Liang  , Feng Jin- Qian  ,   (1)佛山科学技术学院理学院，佛山  528000; (2)西北工业大学理学院，西安  710072
Published: December 2020

In this paper, the p-moment stability of impulsive differential equations is considered. A theory about this problem under a weak condition and an assumption which is more familiar in impulsive system is proved. As an application, the impulsive synchronization of Lorenz system excited by white-noise is considered, the p-moment stability of error system is proved, so the synchronization can be realized using impulsive method under p-moment stability. Numerical simulation verify the feasibility of this synchronization method.
Gravity model for spatial network based on optimal expected traffic
Authors: Qian Jiang-Hai  , Han Ding-Ding  ,   华东师范大学信息科学技术学院通信工程系，上海  200241
Published: December 2020

In this paper, we propose a spatial network model based on the optimal expected traffic. The model maximizes the total expected traffic of the network. By changing two parameters α and γ which represent the dependence of the network on the fitness and geographical constraints respectively, the model can vary its topology from heterogeneous star-like networks to homogeneous road-like networks. We use our model to simulate the Chinese city airline network and compare it with the real data. In the end of the paper, we discuss the relationship of the expected and the real traffic （namely the real weight on the network）.
Phenomenological studies on D0-D0 mixing and strong phase difference
Authors: Lu Gong-Ru  , Cheng Xiao-Dong  ,   河南师范大学物理与信息工程学院，新乡  453007
Published: December 2020

Most recently, both BABAR and Belle experiments found evidences of neutral D mixing. In this paper, we discuss the constraints on the strong phase difference in D0→Kπ decay from the measurements of the mixing parameters y′, yCP, and x at the B-factories. With CP tag technique at ψ（3770） peak, the extraction of the strong phase difference at BES-Ⅲ is discussed. The sensitivity of the measurement of the mixing parameter y is estimated in BES-Ⅲ experiment at ψ（3770） peak. Finally, we make an estimate on the measurements of mixing rate RM.
Influence of wet etching on the morphologies of Si patterned substrates and ZnO epilayers
Authors: Cui Xiu-Zhi  , Zhang Tian-Chong  , Mei Zeng-Xia  , Liu Zhang-Long  , Liu Yao-Ping  , Guo Yang  , Su Xi-Yu  , Xue Qi-Kun  , Du Xiao-Long  ,   (1)曲阜师范大学物理工程学院，曲阜  273165; (2)中国科学院物理研究所，北京  100190; (3)中国科学院物理研究所，北京  100190；清华大学物理系,北京  100084; (4)中国科学院物理研究所，北京  100190；曲阜师范大学物理工程学院，曲阜  273165
Published: December 2020

A ZnO film with two-dimensional periodic structure was grown on Si substrate by radio-frequency plasma-assisted molecular beam epitaxy. The influence of wet-chemical etching on Si (100) and Si (111) substrates patterned with dot arrays was investigated for achieving a ZnO film with good periodic structure. X-ray diffraction and scanning electron microscopy mesurements demonstrate better crystalline quality and surface morphology of ZnO film grown on Si (111) than that on Si (100). The results suggest that the growth method is feasible for the fabrication of ZnO film with good periodic structure.
Study on the frontal condition for continuous phase plate in inertial confinement fusion driver
Authors: Yao Xin  , Gao Fu-Hua  , Zhang Yi-Xiao  , Wen Sheng-Lin  , Guo Yong-Kang  , Lin Xiang-Di  ,   (1)成都精密光学工程研究中心，成都  610041; (2)四川大学物理科学与技术学院，成都  610064
Published: December 2020

Optimal placement for continuous phase plate （CPP） in terminal optical system of the Inertial Confinement Fusion （ICF） driver has been studied. Based on non-linear perturbation and transmitting theory of high power laser, the optical characteristics in near and far fields as well as third harmonic conversion efficiency after passing throngh the frequency conversion system has been calculated. As a result, the third harmonic conversion efficiency and optical characteristics of the emergent light beam are influenced by the CPP which is placed before the frequency conversion system. But if the diameter of the round focal spot in far field is smaller than 05 mm, the decline of the third harmonic conversion efficiency and the rise of contrast ratio are within permitted range, the shape of focal spot in far field and the encircled energy of focal spot also accord with the design requirement at the same time. The CPP which enables small focal spot in far field, when located in the beam path of fundamental frequency of ICF system to smooth and shape the light beam, will not exert influence on the normal running of ICF system.
The effect of nonlinear exposure on bandgap of three-dimensional holographic photonic crystal
Authors: Ren Xiao-Bin  , Zhai Tian-Rui  , Ren Zhi  , Lin Jing  , Zhou Jing  , Liu Da-He  ,   应用光学北京市重点实验室，北京师范大学物理系，北京  100875
Published: December 2020

The effect of nonlinear exposure on the characteristics of photonic crystal fabricated by holography is investigated theoretically and experimentally. A kind of materials with low refractive index （n=152） is used to fabricate diamond structure. By controlling the exposure in strong nonlinear range, the property of photonic bandgap is improved. Also，some proposals are made to achieve complete band gaps by materials with low refractive index.
Study on the performance of stress area mismatched Panda polarization-maintaining fiber
Authors: Yan Feng-Ping  , Wei Yan  , Fu Yong-Jun  , Wei Huai  , Gong Tao-Rong  , Wang Lin  , Li Yi-Fan  , Liu Peng  , Liu Yang  , Tao Pei-Lin  , Qu Mei-Xia  , Jian Shui-Sheng  ,   全光网络与现代通信网教育部重点实验室，北京  100044；北京交通大学光波技术研究所，北京  100044
Published: December 2020

An approximate analytical expression of the stress birefringence for Panda polarization-maintaining fiber (Panda-PMF) was deduced by using elasticity theory and complex function method. Based on this expression, the birefringence properties of this fiber were analyzed numerically by using the finite-element method. The results show that the birefringence expressed by core average stress mode is more accurate than that expressed by the core center stress mode and the error of the former is less than 0.18% compared with that of the analytic method. Further more, the birefringence degradation of the Panda-PMF induced by stress area mismatch was analyzed and proved by the related experiment.
Planar left-handed metamaterials based on double split-ring resonator pairs
Authors: Wang Jia-Fu  , Qu Shao-Bo  , Xu Zhuo  , Zhang Jie-Qiu  , Ma Hua  , Yang Yi-Ming  , Gu Chao  ,   (1)空军工程大学理学院，西安  710051; (2)空军工程大学理学院，西安  710051；西安交通大学电子陶瓷与器件教育部重点实验室，西安  710049; (3)西安交通大学电子陶瓷与器件教育部重点实验室，西安  710049
Published: December 2020

By theoretical analysis and experimental simulation，planar left-handed metamaterials using double split-ring resonator pairs are studied in this paper. Simultaneous negative permittivity and permeability are described and explained by using equivalent circuit theory. Moreover，double split-ring resonator pairs used in the design of 3-dimensional left-handed metamaterials are also investigated. The results show that double split-ring resonator pairs can be used as planar left-handed metamaterials with small sizes and that double split-ring resonator pairs can be also used as 3-dimensional anisotropic magnetic metamaterials to realized negative permeability in 3-dimensional left-handed metamaterials.
Theoretical study on the rule of plasma temperature decay in the process of lightning dissipation
Authors: Zhao Xue-Yan  , Yuan Ping  , Wang Jie  , Shen Xiao-Zhi  , Guo Yi-Xiao  , Qiao Hong-Zhen  ,   西北师范大学物理与电子工程学院，兰州  730070
Published: December 2020

The temporal and spatial distributions of the plasma temperature during the dissipation process of lightning are calculated theoretically by applying the equation of motion，the equation of continuity and the equation of energy conservation of hydrostatics. The result shows that the temperature decay at a given radius is quicker in the earlier stage and slower in the later stage; Furthermore，the higher the original temperature，the quicker the decay. The temperature decays slower when the radius becomes larger. At the same time，the larger the radius of lightning channel，the greater the temperature gradient, and vice versa. According to the time and position of freezing temperature of NO，we can conclude primarily that NOx are produced in the channel of less than 9 mm radius in the time within 50 ms after the lightning return stroke.
Electron-theoretical study of grain refining mechanism of Mg alloys
Authors: Liu Gui-Li  ,   沈阳工业大学建筑工程学院，沈阳  110023
Published: December 2020

The electronic parameters，such as the structural energy and atom binding energy of both α-Mg and α-Zr，the Mg/Zr interface energy and surface energy of Mg，as well as the interaction energies between Zr atoms and between Zr and impurity atoms，were calculated by means of recursion method. The calculated results showed that the structural energy and atom binding energy of α-Zr are lower than those of α-Mg，and the Mg/Zr interface energy is lower than the surface energy of Mg，which，in an energetical point，explains the experimental phenomenon. Specifically，Zr particles first crystallize out of the Mg liquid and then act as heterogeneous nucleation sites to refine the Mg grains. The atom interaction energies indicate that the Zr atoms can attract each other to form Zr atom clusters in Mg，and combine with impurity atoms to form compounds，thus weakening the Mg grain refining effect.
Theorical and experimental research on the HELS method in the cyclostationary acoustic field
Authors: Zhang Hai-Bin  , Wan Quan  , Jiang Wei-Kang  ,   上海交通大学机械系统与振动国家重点实验室，上海  200240
Published: December 2020

Helmholtz equation least square method (HELS) is based on the assumption that the acoustic field can be approximated by the superposition of a series of spherical waves. According to the principle of least square error between the reconstruction and measurement, the expansion number of the spherical wave equation and the related coefficients can be determined by the least-square method. The HELS method is applied in the practice due to its efficient computing and less measurements comparing with other acoustical holography algorithms. HELS and other near-field acoustic holography methods are all based on the stationary acoustic field. As a special example of the non-stationary acoustic field, the cyclostationary acoustic field is usually analyzed by dealing with signals in a single channel and its nth order statistics are often utilized to detect mechanical faults. In the present paper, HELS method is modified to analyze the cyclostationary acoustic field with the variance of cyclic spectrum density. The reconstruction in the appropriate cyclic frequency will supply visible acoustic field information, especially that hidden under the cyclostationary condition. A numerical simulation is done to verify the validity of the modified HELS, in which the effects of the ways of measurement are discussed. At last, a spherical sound box driven by cyclostationary signal is set in a semi-anechoic chamber and the acoustic field is reconstructed by modified HELS method.
Study of corrosion effect of Pt on Ti alloys by recursion method
Authors: Liu Gui-Li  ,   沈阳工业大学建筑工程学院，沈阳  110023
Published: December 2020

The electronic structure parameters of pure Ti and TiPt alloy, such as density of states, Fermi energy level, environment-sensitive embedding energy and order energy have been calculated by recursion method. The environment-sensitive embedding energy induced by Pt in Ti crystal is greater than that on Ti surface, so Pt is prone to gather on Ti surface. The order energy between Pt atoms is positive, which leads Pt atoms to form intermetallics with bulk Ti atoms. The electric potential of intermetallics is lower than that of Ti atom cluster at Ti alloy surface, so cells will form between intermetallics and Ti atom clusters, then the intermetallic will decompose in corrosive medium. With the deposition of Pt, a rough electrocatalytic Pt layer would form on the surface of Ti alloy. This electrocatalytic Pt layer enhances the passivation of Ti alloy and improves the corrosion resistance of Ti alloy.
Gauss principle for a super-thin elastic rod dynamics
Authors: Xue Yun  , Weng De-Wei  ,   上海应用技术学院机械与自动化工程学院，上海  200235
Published: December 2020

The analytical formulation of dynamics of a super-thin elastic rod was studied on the basis of Gauss variation. The definition of virtual displacement in the generalized acceleration space with respect to the arc-coordinate and the time were given with expression of Gauss variation，respectively. The nonholonomic constraint equations of the virtual displacements expressed by Gauss variation were given. The Gauss’s principle of the dynamics of a super-thin elastic rod was established, from which the Kirchhoff equation, the Lagrange equation, the Nielsen equation and the Appell equation of the rod can be derived. The Lagrange equation with indeterminate multipliers was obtained for the case when the rod is subjected to the nonholonomic constraints. The Gauss's principle of least compulsion of a super-thin elastic rod was proved and the compulsion function has a minimum for the actual motion and its physical meaning was indicated.
Optoelectronic characteristics of NPB-based vertical organic light-emitting transistors
Authors: Yang Sheng-Yi  , Du Wen-Shu  , Qi Jie-Ru  , Lou Zhi-Dong  ,   北京交通大学光电子技术研究所，发光与光信息技术教育部重点实验室，北京  100044
Published: December 2020

Vertical light-emitting transistor is a kind of optoelectronic devices combining characteristics of light-emitting and the “on/off” function of transistor, and its channel length can be reduced to nanometers to make it operate at low voltages and high speeds. Holes and electrons injected from source and drain electrodes form excitons in the emissive layer and radiate light. The amount of charge carriers can be controlled by the gate voltage, consequently to control the intensity of light emission. In this paper, by inserting a thin hole-transporting BCP layer at different locations in the device ITO/NPB（40nm）/Al（30nm）/NPB（20nm）/Alq3（55nm）/Al, we explored the reasons of large drain current and the detailed carriers processes in the device by studying the variation of their optoelectronic characteristics. Our experimental data confirmed that holes injected from central Al gate contribute to the current in the channel. Further, LiF thin film was used as a buffer layer to modify the drain electrode, in this way to improve electron injection and reduce drain current. As a result, relatively stable light-emitting transistors were obtained with significant enhancement in light emission, and the emission intensity can be controlled by the gate voltage. The color of the emission light can easily be tuned by using different luminescent materials.
Preparation and laser induced thermoelectric voltage effect of ［（SrTiO3）n/（SrTi0.8Nb0.2O3）m］20/LaAlO3 superlattices
Authors: Qin Yi  , Zhang Hui  , Tan Song-Lin  , Liu Ting  , Zhang Peng-Xiang  ,   昆明理工大学光电子新材料研究所,昆明  650051
Published: December 2020

The （SrTiO3）n/（SrTi0.8Nb0.2O3）m superlattices on vicinal-cut LaAlO3 （100） single crystal substrate with tilting angle 10° have been prepared using pulsed laser deposition. The superlattices were characterized by X-ray diffraction, in which regularly distributed satellite peak structure was observed. According to the position of satellite peaks, the superperiod of superlattices was calculated and the deposition rates of SrTiO3 and SrTi0.8Nb0．2Ｏ3 were deduced as 0.78 /pulse for SrTiO3 and 0.57 /pulse for SrTi0．8Nb0．2Ｏ3. In addition, laser induced thermoelectric voltage （LITV） effect was measured for the first time in these superlattice thin films. This phenomenon indieales that this kind of artificial atomic layer thermopile structure possesses Seebeck anisotropy. It was found that when the thickness of dielectric SrTiO3 layer n=46.8 nm, for conductive SrTi0．8Nb0．2Ｏ3 layer with m=19.0 nm and m=11.4 nm, the average peak voltage of LITV signals reaches the maximum U—P=0.7　V/mJ·mm, and the minimum　average response time is τ—=124 ns, respectively.
Piezoelectricity of laminated polymer films made of nonporous fluoroethylene and porous polytetrafluoroethylene layers
Authors: Zhang Xiao-Qing  , Huang Jin-Feng  , Wang Xue-Wen  , Xia Zhong-Fu  ,   同济大学波耳固体物理研究所,上海  200092
Published: December 2020

The piezoelectrets made of porous polytetrafluoroethylene （PTFE） films and nonporous fluoroethylenepropylene （FEP） films are prepared by using a hot-pressing method. The quasi-static piezoelectric d33-coefficients of such piezoelectret films are measured. The thermal stability of d33-coefficients and dynamic characteristics of charges in the piezoelectret films are investigated. The dynamic d33-coefficients are obtained by analyzing the dielectric resonance spectra of the piezoelectret films. The results show that the piezoelectric d33-coefficients up to 300 pC/N are achieved for the laminated PTFE/FEP films. The d33 value retains 40% of the initial value when the sample was annealed at the temperature of 90℃ for 20 h. Pre-ageing is an effective way to further improve the thermal stability of d33-coefficients. The dominant drift path of the detrapped charges in the shallow traps is most likely along the surface of the PTFE fibers, while charge drift through the solid layer of FEP is possibly prevailing for the charges in the deeper traps. The d33 value determined from the dielectric resonance spectrum is smaller than the quasi-static d33 value, which is mainly due to the enhanced Young's modulus with the increase of frequency.
Dynamics study of the adsorption and diffusion in early growth stage of AlN/α-Al2Ｏ3（0001） films
Authors: Yang Chun  , Feng Yu Fang  , Yu Yi  ,   (1)可视化计算与虚拟实现四川省重点实验室,四川师范大学，成都  610068; (2)可视化计算与虚拟实现四川省重点实验室,四川师范大学，成都  610068；电子薄膜与集成器件国家重点实验室，电子科技大学，成都  610054; (3)四川师范大学学报编辑部自然科学版,成都  610068
Published: December 2020

The research of temperature effect on the surface adsorption and diffusion is an important problem for the initial growth mechanism of AlN/α-Al2Ｏ3（0001） thin films. Using the ab initio molecular dynamics method based on the first principles, the adsorption process, system energy, dynamic track and the diffusion coefficient are calculated at temperatures from 300℃ to 800℃. The results indicate that the adsorption process can be divided into three stages, the physical adsorption, the chemical adsorption and the stable surface growth state. With the temperature increasing, the average diffusivity of the particles at α-Al2Ｏ3（0001） surface is enhanced in the bonding process. The diffusion coefficient of N atom is higher than that of the Al atom, especially in the physical adsorption stage. At higher temperatures （over 700℃）, the role of desorption of the N atom is markedly strengthened, so it is unfavorable to the stable absorption of AlN. The temperature between 500℃ and 700℃ is beneficial to the stable adsorption and the growth of the AlN on α-Al2Ｏ3（0001） surface.
A novel local-world evolving network model for power grid
Authors: Wang Guang-Zeng  , Cao Yi-Jia  , Bao Zhe-Jing  , Han Zhen-Xiang  ,   (1)浙江大学电气工程学院，杭州  310027; (2)浙江大学电气工程学院，杭州  310027；湖南大学电气与信息工程学院，长沙  410082
Published: December 2020

Many systems in the real world can be described by evolving models of complex network, one of which is power system. Classical network models show great inconsistence with practical power grids. Based on the essential evolution characteristics of power grid, we propose a new local-world evolving network model for complex power grid, which exists in many physical complex networks. The statistical properties and dynamics of the proposed model are analytically studied. It is found that the degree distribution of this new model has a power-law tail, and its scaling exponent is between 3 and ∞. Numerical simulations for West American power grid and North China power grid and their comparison with random network and scale-free network indicate that the new evolving network model captures the essential features of real-world power grid. Furthermore, it is proved that power grid is neither a random network nor a scale-free network.
The transformation between the Eulerian and Lagrangian solutions for irrotational standing gravity waves
Authors: Chen Yang-Yih  , Hsu Hung-Chu  ,   (1)国立成功大学水工试验所，台南  709; (2)国立中山大学海洋环境及工程学系，高雄  804
Published: December 2020

This study reports the transformations between the third-order Eulerian and Lagrangian solutions for the standing gravity waves on water of uniform depth. Regarding the motion of a marked fluid particle, the instantaneous velocity, the mass conservation and the free surface must be the same for either Eulerian or Lagrangian methods. We impose the assumption that the Lagrangian wave frequency is a function of wave steepness. Expanding the unknown function in a small perturbation parameter and using a successive expansion in a Taylor series for the water particle path and the period of a particle motion, we obtain the third-order asymptotic expressions for the Lagrangian particle trajectories and the period of particle motion directly in Lagrangian form. In particular, the Lagrangian mean level which differs from that in the Eulerian approach is also found as a part of the solutions. Therefore, the given Eulerian solutions can be transformed into the completely unknown Lagrangian solutions and the reversible process is also identified.
Spatiotemporal shaping and filtering of terahertz pulses through metal slits with finite thickness
Authors: Liu Hai-Liang  , Zhang Tong-Yi  , Zhu Shao-Lan  , Fan Wen-Hui  ,   (1)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; (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；中国科学院研究生院,北京  100049
Published: December 2020

The characteristics of spatiotemporal shaping and filtering of terahertz （THz） pulses passing through metal slits with finite thickness have been investigated by employing the finite-difference time-domain （FDTD） method. It is shown that this diffraction-based quasi-optical technique has a good influence on shaping and filtering of transverse magnetic（TM） polarized THz pulse, while has no effect on transverse electric（TE） polarized THz pulse. Furthermore, the numerical simulation results have been interpreted qualitatively by the planar waveguide theory and can be employed in the relevant experiments.
Evolution and controlled manipulation of a Bose-Einstein condensate chirped soliton in external potentials
Authors: Zong Feng-De  , Yang Yang  , Zhang Jie-Fang  ,   浙江师范大学非线性物理研究所，金华  321004
Published: December 2020

An extended variational method for describing the dynamics of a Bose-Einstein condensate （BEC） chirped soliton in the presence of periodic and harmonic potentials is developed. It is shown that the BEC chirped soliton dynamics can be deduced via the extended variational method to a set of four coupled nonlinear differential equations. This deduced set of equations agrees remarkably well with full numerical simulations and highlights the dominant physical interactions in the system, namely amplitude, width, chirp, center-position, and center-frequency dynamics. The extended analytic theory provides a useful, accurate, and greatly simplified description of the governing BEC chirped soliton dynamics. It further gives the critical strength ratio of periodic to harmonic potential necessary to support multiple stable lattice sites for the BEC chirped soliton and demonstrates that the BEC chirped soliton can move selectively from one lattice site to another by simply manipulating the potentials. In addition, some interesting results for the experiments and applications of the BEC are also obtained.
Remote state preparation with bipartite entangled states in noisy environments
Authors: Liang Hua-Qiu  , Liu Jin-Ming  ,   (1)华东师范大学物理系精密光谱科学与技术国家重点实验室，上海  200062; (2)华东师范大学物理系精密光谱科学与技术国家重点实验室，上海  200062；台州学院物理与电子工程学院物理系，台州  318000
Published: December 2020

We investigate the influence of quantum noises on the processes of remote preparation of a qubit by using an Einstein-Podolsky-Rosen （EPR） state and a bipartite partially entangled state as the quantum channel respectively. By solving the master equation in the Lindblad form, we obtain the time evolution of the quantum channels. Then we use the trace distance to describe how close the output state and the initial state are in various noisy conditions. Our results show that the influence of the noise acting on z direction is the weakest, and the influence of the noises acting simultaneously on x, y, and z directions is the strongest.
High temperature Raman spectra and micro-structure of LiB3O5 crystal and its melt
Authors: Zhang Xia  , Wan Song-Ming  , Yin Shao-Tang  , You Jing-Lin  , Zhang Rong-Bo  ,   (1)上海市钢铁冶金新技术开发应用重点实验室，上海大学，上海  200072; (2)盐城工学院材料学院，盐城  224003; (3)盐城工学院材料学院，盐城  224003；中国科学院安徽光学精密机械研究所，合肥  230031; (4)中国科学院安徽光学精密机械研究所，合肥  230031
Published: December 2020

The High temperature Raman spectra of LBO crystal and melt were studied. The rule of structure change of BGO crystal with increasing temperature was analyzed. The results show that the peaks of spectra move to the lower wavelength and broaden in different degrees. The intensities of spectra peaks decrease，too. In addition，the phase transformation of LBO crystal was studied by using high temperature Raman spectra as well. There is an apparent phase transformation of LBO at 1100K.
Projective synchronization of fractional-order chaotic systems based on sliding mode control
Authors: Liu Ding  , Yan Xiao-Mei  ,   西安理工大学自动化与信息工程学院，西安  710048
Published: December 2020

For the projective synchronization of fractional-order chaotic systems，a controller based on active sliding mode theory is presented. Based on the stability theory of fractional-order linear system，stability of the proposed method is analysed. Two cases of projective synchronization，i.e.identical fractional-order Liu-Liu systems and different fractional-order Chen-Liu systems，are implemented separately. The simulation results show the effectiveness of the proposed controller.
Tracking control and projective synchronization in the fifth-order hyperchaotic circuit system based on accelerated factor
Authors: Li Chun-Lai  , Luo Xiao-Shu  ,   (1)广西师范大学物理与电子工程学院，桂林  541004; (2)湖南理工学院物理与电子信息系，岳阳  414006
Published: December 2020

A nonlinear controller is proposed to acquire generalised projective synchronization and arbitrary trajectories of full states of a fifth-order hyperchaotic circuit system. By adjusting the scaling factor and the accelerated factor, generalized projective synchronization between the fifth-order hyperchaotic circuit system and the hyperchaotic systems,chaotic systems and periodic signal can be rapidly realised, and the fifth-order circuit's hyperchaotic circuit system can also be driven to arbitrary periodic orbits or fixed point rapidly. Simulation results are presented to demonstrate the effectiveness of the proposed method.
Coherent entangled state representation for the common eigenvector of p1-p2 and a1+a2 and its characteristics
Authors: Li Hong-Qi  , Xu Shi-Min  , Xu Xing-Lei  , Jiang Ji-Jian  ,   菏泽学院物理系,菏泽  274015；菏泽学院量子信息与物理计算重点实验室，菏泽  274015
Published: December 2020

The new two mode coherent entangled state representation 1p,β〉 is proposed by the technique of integration within an ordered product of operators. Its characteristics and mechanism are analysed. The results show that, the common eigenvector |p,β〉 of p1-p2 and a1+a2 exhibits both the characteristics of the coherent state and entangled state. The 1|p,β〉 makes up a new quantum mechanical representation and possesses the completeness relation. The ideal single-mode squeezed state |p=0〉2=exp［1/2a+22|0〉2 and the vacuum state |0〉1 overlapping on a beam splitter may produce the coherent entangled state |p,β〉at the output by the modulation of the laser field.
Measurement and calculation of specific heat for a liquid Ni-Cu-Fe ternary alloy
Authors: Chen Le  , Wang Hai-Peng  , Wei Bing-Bo  ,   西北工业大学应用物理系，西安  710072
Published: December 2020

The specific heat of liquid Ni60Cu20Fe20 ternary alloy was measured by electromagnetic levitation drop calorimetry in the temperature range from 1436 to 2008K. The maximum undercooling achieved in experiment is 232K (0.14TL). The specific heat was determined as 33.27J·mol-1·K-1 which varied slightly with temperature. Furthermore，the temperature dependence of the specific heat of normal and undercooled liquid Ni60Cu20Fe20 alloy was calculated by molecular dynamics method with embedded-atom potential (EAM) and quantum Sutton-Chen many-body potential (QSC). The calculated results indicate that the specific heat increases slowly with the decrease of temperature. By comparing these theoretical calculations with experiments，we found that the QSC model is more reasonable for predicting the specific heat of liquid Ni60Cu20Fe20 alloy than the EAM model.
Laser beam addition of planar waveguides with fractional self-imaging
Authors: Xiao Ling  , Cheng Xiao-Jin  , Xu Jian-Qiu  ,   中国科学院上海光学精密机械研究所，上海  201800
Published: December 2020

Propagation characteristics of laser beams are examined in fractional self-imaging planar waveguides. A potential approach to laser beam combining is proposed by application of planar waveguides with fractional self-imaging. The influences of phase mismatch between laser beams on laser beam addition are discussed. The numerical simulation for two lasers with average power of 300 W shows that the beam addition in fractional self-imaging planar waveguide can improve the parameter M2 of combined beam effectively. The sensitivity of beam addition to the phase mismatch between laser beams has been reduced obviously.
Calculation of the optical path difference and fringe location in polarization interference imaging spectrometer
Authors: Mu Ting-Kui  , Zhang Chun-Min  , Zhao Bao-Chang  ,   (1)西安交通大学理学院，西安  710049; (2)中国科学院西安光学精密机械研究所空间光学实验室，西安  710068
Published: December 2020

The principle of a polarization interference imaging spectrometer based on Wollaston prism is presented. The accurate optical path difference, splitting angle and fringe location plane of single Wollaston prism in four different conditions are calculated by wave-normal tracing method, and the theoretical formulas are introduced. The accurate values and approximate values of the optical path difference, the splitting angle, the fringe location are compared by computer simulation. The results show that the influences of wedge angle, incident angle and incident position on the accurate values and the approximate values are greatly different. The selection range of the wedges angle and the incident angle are deduced according to the accurate value, and the deviation of fringe location plane and its influence on Fourier transform lens are analysed. This study provides a theoretical and practical guidance for the study, design, modulation, experiment and engineering of the polarization interference imaging spectrometers.
Phase-field modeling of free dendritic growth with adaptive finite element method
Authors: Chen Yun  , Kang Xiu-Hong  , Li Dian-Zhong  ,   中国科学院金属研究所，沈阳材料科学国家(联合)实验室，沈阳  110016
Published: December 2020

A simple derivation of phase-field model for pure materials based on entropy functional is provided and then solved by adaptive finite element method (AFEM) to simulate the free dendritic growth from undercooled nickel melt. To investigate the evolutions of the dendrite and reproduce the real physical process，the modeling is performed in a larger domain and thinner interface with the highly computationally efficient and accurate AFEM. The simulated results show that the secondary arms grow in an unsymmetrical mode and their development is controlled by the thermal diffusion and affected by noises which are arbitrarily introduced in the phase-field governing equation. As the latent heat released during the migration of solid-liquid interface is accumulated sufficiently，it prompted initiation of other secondary arms at the same side of the primary arm. As the computation proceeds，the secondary arms become coarsened apparently through four different modes.
Mechanism of dual-wavelength oscillation in Nd:YAG Q-switched laser
Authors: Lin Yan-Feng  , Zhang Ge  , Zhu Hai-Yong  , Huang Cheng-Hui  , Li Ai-Hong  , Wei Yong  ,   (1)中国科学院福建物质结构研究所光电材料化学与物理重点实验室，福州  350002; (2)中国科学院福建物质结构研究所光电材料化学与物理重点实验室，福州  350002；中国科学院研究生院，北京  100049
Published: December 2020

The oscillation mechanism of dual-wavelength Nd:YAG Q-switched laser with two-mirror resonator is studied on the basis of the rate equation. The characteristics of the dual-wavelength laser are discussed by analysing the competition process with different transmissivities. Results show that the oscillating time of the Q-switched pulse laser for 1319nm laser is delayed relative to that of 1064nm. The 1319nm Q-switched laser is formed finally from the first relaxation oscillation spike after the Q-switch opening, i.e. it restrains the rest relaxation oscillation spikes. The transmissivity of relatively balanced output energy is theoretically obtained.
Mutual injection phase-locking of two double clad fiber lasers
Authors: Liu Yang  , Cheng Yong  , Xu Li-Xin  , Zheng Rui  , Wang Xiao-Bing  , Wang Hui-Sheng  , Lu Chang-Yong  , Sun Bin  ,   (1)武汉军械士官学校光电研究所,武汉  430075; (2)中国科技大学物理系,合肥  230026
Published: December 2020

A novel mutual injection phase-locking fiber laser combining technique is proposed， based on a corner-cube and a beam splitter with reflectivity of 50% at 45°， and the mutual injection phase-locking principle is introduced. Mutual injection phase-locking of two individual double clad fiber lasers is experimentally realized, steady interference stripes with high contrast ratio（about 0.57）are observed and more than 10W output power is obtained, which indicates that the power combining efficiency is 76%. Successful attempts of phase lock show that this mutual injection-locking method is a promising technology in the field of fiber laser coherent and the output power can be further scaled.
Design of high polarization and single-mode photonic crystal laser
Authors: Chen Wei  , Xing Ming-Xin  , Ren Gang  , Wang Ke  , Du Xiao-Yu  , Zhang Ye-Jin  , Zheng Wan-Hua  ,   中国科学院半导体研究所纳米光电子实验室,北京  100083
Published: December 2020

The dipole mode in triangular photonic crystal single defect cavity is degenerate. By deforming the lattice in photonic crystal we can obtain non-degenerate dipole modes. Lattice deforming in the whole photonic crystal destroys the characteristic of symmetry, so the distribution of the electromagnetic field is affected and the polarization of the electromagnetic field is also changed. Lattice deforming divides the degenerate dipole mode into the x-dipole mode and the y-dipole mode. It is found that the non-degenerate modes have better properties of polarization. So the high polarization and single dipole mode photonic crystal laser can be achieved by deforming the lattice of photonic crystal. In this paper, we simulated the cavity in photonic crystal slab and mainly calculated the quality factor of x-dipole mode under different deforming conditions and with different filling factors. The properties of polarization of x-dipole and y-dipole modes are also calculated. It is found that the ratio of intensities of Ex to Ey in x-dipole mode and that of Ey to Ex in y-dipole mode are 44 and 27, respectively.
Design and simulation of left-handed-property structure based on parallel metallic slabs
Authors: Zhang Song  , Qu Shao-Bo  , Ma Hua  , Xie Feng  , Xu Zhuo  ,   (1)空军工程大学理学院,西安  710051; (2)空军工程大学理学院,西安  710051；西安交通大学电子材料与器件教育部重点实验室,西安  710049; (3)西安交通大学电子材料与器件教育部重点实验室,西安  710049
Published: December 2020

The structure of the parallel metallic slabs with middle-part-indentation is based on the parallel metallic wires. The permittivity of the structure is negative in a certain frequency range because of the effect of the plasma. And the strong magnetic resonance occurs in the special frequency range because the middle-part-indentation is introduced in the parallel metallic slabs. The result of simulation shows that the structure composed of ceramic alumina has negative permittivity and permeability in the X-band. The range of the double negative （εμ<0） varies with the resonance frequency. Theoretical analysis, which is in agreement with the results of simulation, indicates that the resonance frequency is related with the width of metallic slaps, height of indentation and the width of the middle-part of the structure.
Measurement of the carrier-envelope phase stability of infrared femtosecond laser pulses by two-path interferometer
Authors: Wang Jian-Liang  , Zhang Chun-Mei  , Song Li-Wei  , Leng Yu-Xin  ,   中国科学院上海光学精密机械研究所强场激光物理国家重点实验室, 上海  201800
Published: December 2020

We describe a self-referencing two-path interferometer designed to measure the carrier-envelope phase stability. In experiment, we measure the carrier-envelope phase （CEP） stability of a home-made infrared tunable OPA laser pulses with the self-referencing two-path interferometer. When the wavelength of the incident pulses is 1.6 μm, the CEP fluctuation is 115 mrad （rms） in 100 seconds. The interferometer can provide an accurate and quick measurement of the pulse CEP.
Design of Rugate filter for gain narrowing compensation
Authors: Zhao Lei  , Sui Zhan  , Zhu Qi-Hua  , Zhang Ying  , Zuo Yan-Lei  ,   (1)中国工程物理研究院激光聚变研究中心,绵阳  621900; (2)中国工程物理研究院激光聚变研究中心,绵阳  621900；中国工程物理研究院研究生部, 绵阳  621900
Published: December 2020

Two Rugate filters for compensating gain narrowing are designed separately based on the gain characteristics of Ti: sapphire amplifier and Nd: glass amplifier. The Gauss spectral shaping function is selected as the compensation modulation function. Characteristic matrix method is used to analyse the spectral response of the Rugate filter approximately. Amplification using Rugate filter spectral compensation is analysed numerically. Results show that they satisfy the compensation requirements well and can be used as the spectral compensation filters.
Ultrasonic enhancement of interaction between liposome and cell
Authors: Zhang Chun-Bing  , Qiu Yuan-Yuan  , Xi Xiao-Yu  , Zhang Dong  ,   (1)江苏省中医院检验科,南京  210029；南京大学声学研究所近代声学教育部重点实验室,南京  210093; (2)南京大学声学研究所近代声学教育部重点实验室,南京  210093
Published: December 2020

The interaction between liposomes and cells under ultrasound exposure was theoretically and experimentally studied. We experimentally developed liposomes containing fluorescent materials, and measured the efficiency of drug delivery in a suspension containing liposomes and cells under 1 MHz ultrasound excitation for 40 s. Results demonstrated that the sonicated samples were superior to the control group （without ultrasound） in absorbing fluorescent materials and the capacity was improved by 8.78% under the excitation of ultrasound at an acoustic pressure amplitude of 0.24 MPa. Finally, the potential mechanisms of ultrasound enhancement was discussed with respect to the changes of velocity and diameter of liposomes induced by ultrasound.
Experimental diagnosis of electron density of laser induced air plasma by interferometry
Authors: Zhang Hong-Chao  , Lu Jian  , Ni Xiao-Wu  ,   南京理工大学应用物理系,南京  210094
Published: December 2020

High quality interference pattern was obtained with a modified Mach-Zehnder interferomenter. An FFT analysis is applied to extracting the phase of the reconstructed interferograms, and then the inverse Abel transformation is used to calculate the three-dimensional electron density distribution. The electron density and the plasma expanding velocity at various delay times were obtained. The results show that the formation of the plasma channel in the early stage of the laser induces air plasma, and the rapid decrease of the plasma expanding velocity accelerates the collapse of the plasma channel. At about 48 nanosecond time, the eccentricity of the plasma shape reaches the maximum value and then evolves to a circular shape.
Effect of 100 keV proton irradiation on photoemission of GaAs/Ge space solar cells
Authors: Zhao Hui-Jie  , He Shi-Yu  , Sun Yan-Zheng  , Sun Qiang  , Xiao Zhi-Bin  , Lü Wei  , Huang Cai-Yong  , Xiao Jing-Dong  , Wu Yi-Yong  ,   (1)哈尔滨工业大学空间材料与环境工程实验室，哈尔滨  150001; (2)中国电子科技集团第18研究所，天津  300381
Published: December 2020

The experiment of GaAs/Ge solar cells co-irradiated by proton and electron was done in space environment simulation equipment. The materials of GaAs/Ge solar cell are irradiated by proton beam with fixed energy of 100keV and dose from 1×109 to 3×1012cm-2. The I-V characteristic，spectral response and photoluminescence (PL) spectra were measured before and after irradiation in order to study the cells performance degradation induced by irradiation. The result indicated that the parameters such as short circuit current (Isc)，open circuit voltage (Voc)，maximum output power (Pmax) and fill factor (FF) all suffer degradation at different degrees as the irradiation fluence increases. The results show that proton irradiation induces a great damage in optical characteristics of the solar cell，resulting from the large quantity of irradiation defects that would destroy crystal lattice integrity and reduce the diffusion distance of minority carrier，and thus increase the surface recombination velocity. The damage extent of GaAs/Ge solar cell increases with proton dose in the ranges under investigation.
A density functional theory study of the absorption behavior of copper on single-walled carbon nanotubes
Authors: Zhang Bian-Xia  , Yang Chun  , Feng Yu-Fang  , Yu Yi  ,   (1)四川师范大学可视化计算与虚拟现实四川省重点实验室,成都  610068；电子科技大学电子薄膜与集成器件国家重点实验室，成都  610054; (2)四川师范大学可视化计算与虚拟现实四川省重点实验室,成都  610068；四川师范大学化学与材料科学学院,成都  610068; (3)四川师范大学学报编辑部自然科学版,成都  610068
Published: December 2020

The absorption behavior of copper atoms on the armchair （5,5） single wall carbon nanotube is investigated by the density functional theory. It is shown that the absorption on the outside nanotube is energetically preferred to that on the inside nanotube, Morever, the adsorbed copper atom on the top of carbon is more stable than that on the other outside sites. At the same time, the characteristic of the forming bond on the top of carbon between copper and SWNT is detailed. The absorption behavior belongs to chemical absorption, and based on the analysis of frontier orbital, it is shown that the new σ bond is mainly due to the interaction of 4s valence state of copper and coupling σ-π bond of SWNT. Furthermore, the calculated electron densities of two representative adsorption positions show that electron clouds overlap more on the top of carbon adsorbed copper atom， which　further confirms that copper and carbon atoms can form chemical bond in a sense.
Crystallization mechanism of Fe-based nanocrystalline alloy
Authors: Yang Quan-Min  , Xu Qi-Ming  , Fang Yun-Zhang  , Mo Chan-Juan  ,   (1)西安建筑科技大学材料科学与工程学院,西安  710055; (2)西安建筑科技大学材料科学与工程学院,西安  710055；连云港师范高等专科学校物理系，连云港  222006
Published: December 2020

Based on the atomic force microscope observation of the three-dimensional mesostructure of Fe73.5Cu1Nb3Si13.5B9 alloy ribbon annealed at different temperatures, on the basis of experimental results of X-ray diffraction and the Mssbauer spectroscopy and theoretical results for this alloy ribbon, we systematically investigate the crystallization process of this alloy ribbon annealed at different temperatures, and propose a number of new concepts, such as the mesostructure with two-kinds of Nb-B framework, the agglomeration phase of the nanocrystalline grains, and the average numbers of nanocrystalline grains in unit volume. Finally, a hypothesis of the crystallization mechanism and the mesostructure model describing the crystallization process of this alloy are established. This model can be evolved to the two- or three-phase structure model.
The elastic constants of polycrystalline materials with cubic system structural single crystals
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

New physical parameters “Y elastic constants" and their physical meanings are proposed at the first time. The Y elastic constants are applied to the polycrystalline materials with cubic system structural single crystals, and they are deduced and compared with the “X-ray elastic constants" of polycrystalline materials with cubic system structural single crystals. The expressions of mechanical elastic constants of polycrystalline materials based on Y elastic constants are in good agreement with that proposed by Krner.
An XPS study on the structure of SiNx film deposited by microwave ECR magnetron sputtering
Authors: Ding Wan-Yu  , Xu Jun  , Lu Wen-Qi  , Deng Xin-Lu  , Dong Chuang  ,   (1)大连交通大学光电材料与器件研究所，大连  116028；大连理工大学三束材料改性国家重点实验室，大连  116024; (2)大连理工大学三束材料改性国家重点实验室，大连  116024
Published: December 2020

Hydrogen-free SiNx films were deposited at N2 flow rate ranging from 1 sccm to 20 sccm by microwave electron cyclotron resonance plasma enhanced unbalance magnetron sputtering system. We studied the influence of N2 flow rate on the structural characteristics of deposited films in chemical structure, stoichiometry, composition at different depths in film, and hardness by using X-ray photoelectron spectroscopy and nano-indantation. The results indicate that the films deposited at low N2 flow rate are Si-rich structure. The films deposited at 2 sccm N2 flow rate show an excellent stoichiometry with 94.8% Si—N bond content and uniformity of composition in different depths. At the same time, the films display the highest hardness value of 22.9 GPa. The films deposited at high N2 flow rate contain too much N—Si—O bond and Si—O bond, which is caused by chemical absorption both on and in film in atmosphere. The films present N-rich structure. In this situation, the films display poor mechanical properties with hardness of only 12 GPa.
Room-temperature photoluminescence analysis of nano-β-FeSi2/a-Si multilayer films
Authors: Niu Hua-Lei  , Li Xiao-Na  , Hu Bing  , Dong Chuang  , Jiang Xin  ,   大连理工大学材料科学与工程学院，三束材料改性国家重点实验室，大连  116024
Published: December 2020

Nano-β-FeSi2/a-Si layered structure was successfully deposited on Si （001） substrates using radio-frequency magnetron sputtering method. X-ray diffraction, transmission electron microscopy and photoluminescence （PL） analyses were used to characterise the structure, composition and photoluminescence properties of β-FeSi2/Si multilayer films. The results show that the peak at wavelength of 1.53 μm is observed from Fe/Si multilayer films by PL at room temperature. Without annealing, The films are of （amorphous FeSi2+ Nano-β-FeSi2 particles） / amorphous Si structure, whereas after annealing, the films are of β-FeSi2 particles/（crystal Si + amorphous Si） structure. Furthermore, the same PL intensity between as-grown and annealed samples indicates that identical luminescence property can be excited from amorphous FeSi2+β-FeSi2 particles and β-FeSi2 particles. In this experiment, the peak at wavelength of 1.53 μm is also a further indication of the semiconducting properties of amorphous FeSi2.