bluuebunny/crossref_metadata_2025 huggingface dataset:
Discussions again on the temperature and entropy of non-stationary black holes
Authors: Qiang Li-E  , Gao Xin-Qin  , Zhao Zheng  ,   北京师范大学物理系，北京 100875
Published: December 2020

A new tortoise coordinate transformation is defined. With the thin film model , we calculate again the temperature and the entropy of non_stationary black holes. The problem of indetermination of the cut_off factor in calculating the entr opy of non_stationary black holes is solved. We study and understand again the t emperature and the entropy of non_stationary black holes by way of the Vaidya b lack hole and the rectilinearly accelerating black hole.
Numerical simulation and analysis on the mechanical behaviors of the single-crystalline and poly-crystalline nano-Cu film
Authors: Xu Zhou  , Wang Xiu-Xi  , Liang Hai-Yi  , Wu Heng-An  ,   中国科学院材料力学行为和设计重点实验室,合肥　230026；中国科学技术大学力学和机械工程系,合肥　230026
Published: December 2020

Molecular dynamics simulation and analysis are performed on the mechanical properties of mono-and poly-crystalline nano-Cu film. Computational results indicate that the temperature effects are very significant on the tensile strength and the deformation mechanism of the mono-crystalline Cu-film. The strength of the sample is much higher at absolute zero temperature than at normal temperature. The plastic deformation at zero temperature is induced by the short-distantce sliding of the particles while it is caused by the long-distance propagation of dislocations at normal temperature. The strength of polycrystalline Cu-film increases with the decrease of grain size. In the process of strain accretion, grain boundary sliding dominates the plastic deformation. Dislocations originating from grain boundaries propagate toward grains. The area of the grain boundary enlarges and the grain size shrinks with the development of plastic deformation. However, the shapes of the basic grains have no remarkable change even at very large strain.
Application of resonant parametric perturbation to the chaos control in Boost converter and its optimization
Authors: Zhou Yu-Fei  , Chen Jun-Ning  , C.K.Tse  , Ke Dao-Ming  , Shi Long-Xing  , Sun Wei-Feng  ,   (1)安徽大学电子工程系,合肥　230039; (2)东南大学电子工程系,南京　210096; (3)香港理工大学电子与资讯工程学系,香港
Published: December 2020

The method of resonant parametric perturbation is a simple non-feedback chaos control means. It is such a suitable control method for controlling chaos in non-autonomous systems that we are inspired to study its applications for chaos control in current controlled Boost converter. Furthermore, the method of resonant parametric perturbation is optimized by selecting the best perturbation phase, so as to achieve the best chaos control results. These relative applications (with or without optimization) in Boost converter can be analyzed theoretically, and the influence induced by variable circuit parameters on the effective perturbation can also be calculated or predicted.
Influence of hydrogen additive and excitation circuits on the output performance of barium vapor laser
Authors: Pan Bai-Liang  , Mao Bang-Ning  , Chen Gang  , Fang Ben-Min  , Yao Zhi-Xin  ,   浙江大学物理系，杭州  310027
Published: December 2020

The output performances of barium vapor laser with and without hydrogen additive excited by pulsed discharge with Blumlein circuit were experimentally investiga ted. The result indicates that the laser output power increases two times with 1.5% hydrogen mixed into the neon buffer gas. Based on this experimental result,this paper further compares the working characteristics of barium vapor laser w ith interactive circuit and Blumlein circuit, and finds that the interactive cir cuit can greatly improve the laser output power and its efficiency. The maximum laser power of 3W and efficiency of 0.4% have been obtained at 1.5μm laser line. The dependence of laser power on working parameters is measured and discuss ed, and the mechanisms of hydrogen additive and interactive circuit for impr ovement of the laser performance are qualitatively analyzed.
Interaction of photovotaic spatial solitons between dark and dark as well as dark and bright
Authors: Jiang De-Sheng  , Ouyang Shi-Gen  , She Wei-Long  ,   中山大学光电材料与技术国家重点实验室，广州\ 510275
Published: December 2020

The parallel interaction between two photovoltaic spatial solitons of dark and dark as well as dark and bright with different wavelengths is investigated by numerical method. Our numerical study indicates that the dark solitons can both remain as quasi soliton form in certain distance while they propagate coaxially. H owever,they attract each other while closely overlapping. And they have a conver gent effect on each other at the slowly varying region of optical field while in larger separations. For the case of interaction between dark and bright, the br igh t one may experience compression, expansion or energy transfer depending on thei r mutual separation.The physical interpretation of this solitons interaction is also given in terms of the refractive index waveguide they jointly induce.
Wavelength demultiplexer using the spatial dispersion of repeated-period double-chirped structures*
Authors: Qin Xiao-Yun  , Huang Bi-Qin  , Chen Hai-Xing  , Yang Li-Gong  , Gu Pei-Fu  ,   浙江大学现代光学仪器国家重点实验室，杭州　310027
Published: December 2020

Based on the rudimentary double-chirped stack, exploiting wavelength-dependent penetration depth, repeated-period double-chirped structures, in which each couple of Bragg layers is repeated for different times, are presented to increase the spatial linear shift and the beam shifting with different incident wavelength, thus allowing the design of compact thin-film spatial wavelength demultiplexer. We compare the improved structure repeated for n times with the directly double -chirped structure with the same layer number, finding that the former has not only more advantages in theoretical design but a higher tolerance in experiment al fabrication. Besides, we have given the qualitative analysis for the strongosc illation appearing in the spatial dispersion curves when the repeated times of improved double-chirped structure or the wavelength of incident beam are relatively large.
Growth and periodic repeating of travelingwave convection with through-flow
Authors: Li Guo-Dong  , Huang Yong-Nian  ,   北京大学力学与工程科学系，湍流与复杂系统研究国家重点实验室，北京　100871
Published: December 2020

Growth dynamics and spatiotemporal evolutions of one-dimensional tra veling-wave pattern in a binary-fiuid-mixture Reylaigh-Benard convection with extremely weak through-flows are investigated by numerically simulating basic hydr odynamic equations. We show that the system exhibits repeated dynamics of trave lingwave convection, and their repeating periods depend sensitively on the strength of through-flow。
Study of the characteristic of D.C.arc plasma torch*
Authors: Yuan Xing-Qiu  , Li Hui  , Zhao Tai-Zhe  , Wang Fei  , Y u Guo-Yang  , Guo Wen-Kang  , Xu Ping  ,   (1)复旦大学现代物理研究所，上海　200433; (2)中国科学技术大学热科学与能源工程系，合肥　230027; (3)中国科学院等离子体物理研究所，合肥　230031
Published: December 2020

The magnetohydrodynamic model,which describes the plasma flows inside the D.C.ar c plasma torch,is presented.By numerical simulations,the plasma flow characteris tics inside the plasma torch and the turbulence effects on the flows are studied in detail.Then the parameter studies are carried out.At last,comparisons betwee n the numerically predicated results and the experimental data are made in detail.
Diffusion of Co in Zr＿46.75Ti＿8.25Cu＿7.5Ni＿10Be＿27.5 bulk metallic glass in supercooled liquid region under high pressure
Authors: Wang Xiu-Ying  , Sun Li-Ling  , Liu Ri-Ping  , Yao Yu-Shu   , Zhang Jun  , Wang Wen-Kui  ,   (1);燕山大学河北省亚稳材料制备技术与科学重点实验室，秦皇岛\ 066004中国科学院物理研究所，北京　100080; (2)燕山大学河北省亚稳材料制备技术与科学重点实验室，秦皇岛\ 066004; (3)中国科学院物理研究所，北京　100080
Published: December 2020

Diffusion of Co in Zr＿46.75Ti＿8.25Cu＿7.5Ni＿10Be＿27.5 bulk metallic glass under high pressure is investigated in supercooled liquid regio n by ion implantation combined with secondary ion mass spectroscopy.Before impla ntation of Co atoms,the amorphous samples were annealed and relaxed in supercool ed liquid region.Diffusion coefficients of Co at 603K in the relaxed samples are found to increase with increasing pressure.And the activation volume for diffus ion is obtained to be -1.236Ω,where Ω is the mean atomic volume of the alloy.The result shows that diffusion of Co in this case is in an interstitial way.
Studies on the transport behavior of Ag/TCNQ thin films*
Authors: Xie Heng-Bo  , Jiang Yi-Ming  , Guo Feng  , Liu Ping  , Li Jin  ,   复旦大学材料科学系，上海　200433
Published: December 2020

Ag/TCNQ bi-layer films with different thickness were prepared on glass substrates by alternating vacuum deposition of Ag and TCNQ. The transport behavior in the film was studied using transmission spectrum to monitor the process. An ab normal accelerated transport phenomenon was observed when the film was ultra thin and a tunneling model was proposed to explain this phenomenon.
Study of interface trap states of AlN-Si(111) heterostructure*
Authors: Zhou Chun-Hong  , Zheng You-Dou  , Deng Yong-Zhen  , Kong Yue-Chan  , Chen Peng  , Xi Dong-Juan  , Gu Shu-Lin  , Shen Bo  , Zhang Rong  , Jiang Ruo-Lian  , Han Ping  , Shi Yi  ,   (1)v南京大学江苏省光电信息功能材料高技术研究重点实验室，物理系,南京　210093; (2)南京大学江苏省光电信息功能材料高技术研究重点实验室，物理系,南京　210093
Published: December 2020

The charge trap states of AlN_Si(111) grown by metal_organic chemical, vapor dep osition are studied by the c apacitance spectroscopy of Al_AlN_Si MIS structure. The interface charge trap st ates of AlN_Si heterostructure and discrete trap center in AlN films are studied . The discrete trap center 2.55eV about E_v in AlN film is found. The dist ribution of interface states is continuous in the energy range of Si. The lowest state density N_ss is 8×10^11eＶ^-1cm^-2in the middle of the band gap. The corresponding time constantτ is 8×10^-4s and the cap ture cross section σnis 1.58×10^-14cm^2. T here are three kinds of trap states in the boundary layer of AlN film which caus es the frequency dispersion in the accumulation region of Al_AlN_Si MIS structure.
The antiferromagnetic coupling and interface diffusion in Fe/Si multilayers
Authors: Ni Jing  , Cai Jian-Wang  , Zhao Jian-Gao  , Yan Shi- Shen  , Mei Liang-Mo  , Zhu Shi-Fu  ,   (1)山东大学物理与微电子学院，济南　250100; (2)四川大学材料科学与工程系，成都　610064; (3)中国科学院物理研究所磁学国家重点实验室，北京　100080; (4)中国科学院物理研究所磁学国家重点实验室，北京　100080;四川大学材料科学与工程系，成都　610064
Published: December 2020

The antiferromagnetic coupling in Fe/Si multilayers was investigated with spa cers varying from pure Si to heavy-doped n-type and p-type Si. It was found that interlayer diffusion between Fe and Si occurred even though the multilayers sho wed well-defined layer structure, and the diffusion dominated the hea vy-doped Si, which made no difference at all for the antiferromagnetic coupl ing with different type of Si. Furthermore, the antiferromagnetic coupling in Fe/Si multi lay ers still goes on while the diffusion between Fe and Si layers enhanced and the layer structure was degraded to some extent after annealing.
Study on Raman spectra of Bi_4-xLa_xTi_3O_12-SrBi_4-yLayTi_4O_15 intergrowth ferroelectrics
Authors: Zhu Jun  , Mao Xiang-Yu  , Chen Xiao-Bing  ,   扬州大学物理科学与技术学院，扬州　225002
Published: December 2020

The Raman spectra of lanthanum-doped intergrowt h ferroelectric ceramics Bi_4-xLa_xTi_3O_12-SrBi_4-yLayTi_4O_15［BLT-SBLT(x+y),x+y= 0.00, 0.25,0.50,0.75,1.00,1.25,1.50］achieved at room temperature were inve stiga ted. The results show that La was substituted the Bi ions in the pseudo-perovski te blocks when La content is lower than 0.50 When La content is higher than 0.50, so me of La ions are incorporated into the (Bi_2O_2)^2+ blocks. The inco rporation of La ions into the (Bi_2O_2)^2+ layers would change th e structure of (Bi_2O_2)^2+ and destroy its functions as the insu lating layers and the space charge storage, which leads to the decrease of the remnant polarization. The relaxation characteristics observed in BLT-SBLT(1.50) are consistent with the softening of the mode lower than 30 cm^-1. This in dicates that La-doping may bring about the structural phase transition.
Study on 3D thermoluminescence spectra in sapphire:Mn
Authors: Zhang Chun-Xiang  , Lin Li-Bin  , Tang Qiang  , Luo Da-Ling  ,   (1)四川大学辐射物理及技术教育部重点实验室，成都　610064; (2)中山大学物理系,广州　510275
Published: December 2020

The 3D thermoluminescence(TL) spectra were used to study the defect structure and luminescence mechanism produced by neutron irradiation in sapphire:Mn. The TL spectra of sapphire:Mn irradiated with 1000 Gy60Co γ-rays before n eutron irradiation show a broad wavelength band around 680nm at about 350℃ which may be related to the Mn2+ ions emission, and there is the 695 nm line spectrum which superposes to 680 nm broad band that is emitted from Cr3+ ions. Comparison between the spectra of undopedα-Al2O3 crystal and that of sapphire:Mn shows that the emission spectra of undopedα-Al2O3 at 416nm at about 207℃ related to the relaxation of an electron from the excited 3P state to the ground state 1S of the F center, is seriously suppressed. After neutron irradiation with fluence 1017cm-2, new glow peaks occur at about 150℃,at wavelengths 416 nm, 680 nm and 695 nm. The intensity of the glow peak at 150℃, 695 nm is greatly enhanced compared to that before neutron irradiation. The glow peaks at wavelength 520 nm at about 150℃, 190℃ and 250℃ emitted probably from Mn2+ ions are observed after 1018cm-2 fluence neutron irradiation. This indicates that neutron irradiation produces a quite amount shallow traps and F centers, and that 3D spectra are useful for studying the trap structures and luminescence mechanism.
A nonNoether conserved quantity constructed using form invariance for Nielsen equation of a non-conservativemechanical system
Authors: Xu Xue-Jun  , Mei Feng-Xiang  , Qin Mao-Chang  ,   (1)北京理工大学力学系，北京　100081; (2)北京理工大学力学系，北京　100081浙江师范大学物理系，金华　321004
Published: December 2020

This paper deals with a non-Noether conserved quantity constructed directly by u sing the form invariance for the Nielsen equation of a non-conservative mechanic al system. The definition and the criterion of a non-point form invariance of th e equation, of which the Noether conserved quantity is studied, are established by relying on the total time derivative along the trajectory of the equation. T he condition under which the form invariance can lead to a non-Noether conserved quantity and the form of the conserved quantity are deduced, and three corollar ies in special cases are presented. Two examples are finally given to illustrate the application of the results.
Special solutions of Kirchhoff equations and their Lyapunov stability
Authors: Xue Yun  , Chen Li-Qun  , Liu Yan－Zhu  ,   (1)上海大学理学院，上海市应用数学和力学研究所，上海　200072; (2)上海大学理学院，上海市应用数学和力学研究所，上海　200072上海应用技术学院机械与自动化工程学院，上海　200233; (3)上海交通大学工程力学系，上海　200030
Published: December 2020

The special solutions of the Kirchhoff equations, which are those rela tive to fixed coordinate system, principal coordinate system of a cross section of the rod, and Frenet coordinate system of the central line of the rod, respect ively, are derived in this paper. Lyapunov stability of these solutions is disc us sed by use of theory on the first-approximation stability, and at the same time stability area in parameter's plane is given.
New exact solitary wave solutions to the BBM and mBBM equations
Authors: Taogetusang  , Sirendaoreji  ,   内蒙古师范大学数学科学学院，呼和浩特　010022
Published: December 2020

In this paper, several new exact solitary wave solutions to the BBM and the m BBM equations are constructed explicitly by combined use of a hyperbolic functio n assumption and a new auxiliary ordinary differential equation. This method also can be used to find new solitary wave solutions to other nonlinear evolution equ ations.
Cross-phase modulational instability in fiber link wit h an active optical amplifier*
Authors: Li  Qi-Liang  , Zhu Hai-Dong  , Tang Xiang-Hong  , Li Cheng-Jia  , Wang Xiao-Jun  , Lin Li-Bin  ,   (1)杭州电子工业学院理学院,杭州　310018; (2)杭州电子工业学院通信学院,杭州　310037; (3)杭州电子工业学院通信学院,杭州　310037四川大学物理科学与技术学院,成都　610064; (4)四川大学物理科学与技术学院,成都　610064
Published: December 2020

In this paper, analytical and numerical methods are used t o study cross_phase modulational instability. Firstly, by use of coup led nonlinear Schrdinger equation, we have studied the cross_phase modulation i nstability in the normal and anomalous dispersion fiber links of wavelength divi sion multiplexed system with an active amplifier, when the amplitude is perturbed. Se condly, m aking use of the split step Fourier transform and Monte_Carlo method, we simulat ed the cross_phase modulation instability in active normal and anomalous dispers ion fibers with fluctuation of phase noise. Comparison between the above met hods shows that the results agree with each other.
Theoretical description of four-wave mixing of femtosecond pulses in gas-filled capillary*
Authors: Chen Bao-Zhen  , Huang Zu-Qia  ,   (1)北京师范大学低能核物理研究所,北京　100875; (2)北京师范大学粒子束和材料改性教育部重点实验室，北京　100875
Published: December 2020

The coupled equations of four_wave mixing by femtosecond pulses in gas_filled capillary are derived. Based on the equation s, the in fluence of the walk_off and phase modulation is investigated. It is found that t he discrepancy between the theoretical and experimental results decreases when t he influence of the walk_off and phase modulation is taken into account. At the same time, it is also found that taking the influence of the 3rd harmonic gener ated by the idler light into account is necessary for reducing the discrepancy b etween the theoretical and experimental results.
Electromicrowave device of microwave plasma thruster operating under vacuum condition and its experiment
Authors: Yang Juan  , Mao Gen－Wang  , He Hong－Qing  , Tang Jin－Lan  , Song Jun  , Su Wei－Yi  ,   西北工业大学航天学院，西安　710072
Published: December 2020

In order to tackle the key problems in the experimental study on the microwave plasma thruster, of which the whole system operates under the vacuum condition, and remove the unnecessary energy loss, an electro microwave device operating under atmosphere and vacuum condition has been developed by applying the design technology of the nonlinear power supply, the integration of attenuator and detector, liquid cooling, and after resolving the gas breakdown problems of electro and microwave apparatus. The experimental study on the device with argon and helium as propellant has been carried out. The results show that the output power of microwave is stable， the device can operate under vacuum and atmosphere condition reliably.
Measurement and analysis of the pulsed magnetic field phase lag in the ceramic case
Authors: Wang Xiang－Qi  , Feng De－Ren  , Shang Lei  , Pei Yuan－Ji  , He Ning  , Zhao Tao  ,   中国科学技术大学国家同步辐射实验室，合肥　230029
Published: December 2020

Due to the damping action during the magnetic moment precession, the magnetic flux generated by a pulsed magnetic field commonly will lag behind the field,so the phase of the pulsed magnetic field lags behind after it penetrates a coated metal. For the nonferromagnetic metal, the phaselag is very faint, and owing to the influence of conductor skin effect and eddy current, it can hardly be detected. An experimental method and the result obtained have been presented in this paper.In this method by using an ultrathin coating with zonal stripe to isolate and select an appropriate position to measure, thus the influences of conductor skin effect and eddy current have been reduced to a minimum. An analysis has been presented in this paper.
Preparation and characterization of In-doped p-type SnO2 thin films by solgel dipcoating*
Authors: Ji Zhen-Guo  , He Zhen-Jie  , Song Yong-Liang  ,   浙江大学硅材料国家重点实验室,杭州　310027
Published: December 2020

In doped SnO2 thin films were prepared on quartz substrates by sol-gel dipcoating technique.X-ray diffraction results show that In doped SnO2 films a re of rutile structure.Ultraviolet-visible absorption results show that In_do ped SnO2 films have an optical band gap of about 3.8eV. Hall effect measur ement results show that the hole concentration and the mobility are dependent on both the processing temperature and the In/Sn atomic ratio. It is found that 5.25℃ is the optimum processing temperature to get the highest hole concentration . For an In/Sn atomic ratio between 0.05 and 0.20, hole concentration is almo st proportional to the In/Sn ratio.
Dielectric and piezoelectric properties of Ca3NbGa3Si2O14 crystal*
Authors: Zhao Ming-Lei    , Wang Jin-Feng  , Yuan Duo-Rong  , Wang Zeng-Mei  , Wang Chun-Lei  , Wang Yuan-Xu  ,   (1)山东大学晶体材料国家重点实验室,济南　250100; (2)山东大学物理与微电子学院,济南　250100
Published: December 2020

The dielectric, piezoelectric and some elastic constants of the Ca3NbGa3Si2O14 crystal had been determined by using Ycut and (yxl)30°cut crystal samples.The calculated piezoelectric constants as functions of cut a ngle of (yxl)θ cut were also given. The Ca3NbGa3Si2O14 crystal showed superior piezoelectric properties with relatively large piezoelectric constants (d11=7.93×10-12C/N，d14=-5.88×10-12 C/N) compared with La3Ga5SiO14 crystal.
The effect of oxygen pressure on the dielectric properties of pulsed laser deposited La-doped PbTiO3 thin film*
Authors: Hu Da-Zhi  , Shen Ming- Rong  ,   苏州大学物理科学与技术学院,薄膜材料江苏省重点实验室,苏州　215006
Published: December 2020

Pb0.72La0.28TiO.3(PLT28) thin films have been prepared on Pt/Ti/SiO2/Si substrates by pulsed laser deposition under various oxygen pressu re. Experimental study indicated that the oxygen pressure exerts a strong impact on the microstructure and the dielectric properties of the thin films. The film deposited under an oxygen pressure of 2Pa had a larger dielectric constant an d kept a low dielectric loss. At 10kHz frequency, the dielectric constant was approximately 852 and the dielectric loss was 0.0110 Meanwhile, we found that other La- modified PbTiO3 films have the same relation between dielectric con stant and pressure as the above. Possible explanation is given for this.
The theoretical study of the effects of salt on structure transition of B-DNA to Z-DNA
Authors: Dong Rui- Xin  , Yan Xun-Ling  ,   (1)聊城大学物理科学与信息工程学院,聊城　252059; (2)聊城大学物理科学与信息工程学院,聊城　252059电子科技大学物理电子学院,成都　610054
Published: December 2020

On the basis of our previous elastic model which is related to the salt ion conc entration, we put forth a new model of B-DNA to Z-DNA transition by considerin g interactions of the hydrogen-bond and base-stacking in Z-DNA, and discuss the effects of salt concentration on the structure transition of B-Z and obtain the force extension curves, the probability distribution curve of the folding angle and the critical torque of B-Z transition at various salt concentrations. The results show that Z-DNA appears when salt concentration reaches 2.4mol/L,and the probability of Z-form begins to increase and the torsion of B-Z trans ition decreases with the increase of salt concentration.
A meshless method with complex variables for elasticity
Authors: Cheng Yu-Min  , Li Jiu-Hong  ,   (1)上海大学上海市应用数学和力学研究所，上海  200072; (2)西安理工大学水利水电学院，西安  710048
Published: December 2020

The moving least-square approximation with complex variables (MLSCV) is developed on the basis of moving least-square approximation. The advantages of MLSCV are that the approximation function of a 2-D problem is formed with 1-D basis function, and the meshless method obtained has greater computational efficiency. A meshless method with complex variables for 2-D elasticity is then presented using MLSCV, and the formulae of the meshless method with complex variables are obtained. Compared with the conventional meshless method, the meshless method with complex variables introduced in this paper has greater precision and computational efficiency. Some examples are given.
The ideal velocity field of ship waves on a viscous fluid
Authors: Wu Yun-Gang  , Tao Ming-De  ,   复旦大学力学与工程科学系，复旦大学波散射和遥感信息国家教育部重点实验室，上海  200433
Published: December 2020

The method used by Ursell to solve the problem of ship waves on an inviscid fluid is extended to the viscous case and the ideal velocity filed is deduced. The singularity on two critical lines deduced by employing the steepest descent method to get the asymptotic expression of integral is eliminated. It is convenient for use in the SAR technique.
Discussion on the transformation property between the configuration wavefunction of the equivalent-electron and the Young tableau
Authors: Hu Kun-Ming  ,   商丘师范学院物理与信息工程系，商丘  476000
Published: December 2020

The transformation property between the configuration wavefunction of the equivalent-electron and the Young tableau is pointed out to be unitary but not to be Hermite unitary. And a sign error of the spectrum item wavefunction is presented.
Series solution for relative-rotation motion equation
Authors: Zhao Wu  , Liu Bin  ,   燕山大学，秦皇岛  066004
Published: December 2020

For solving the difficult calculation problem of nonlinear differential equation of motion of complex revolving shaft in relative rotation , a new decoupled equation was proposed by using series method, which expands the nonlinear differential equation into a series of algebraic equations and the series solution is obtained. Based on the result of the research , the veracious speed fluctuation of revolving shaft in relative rotation in practice can be calculated for the steady state. The method also provides a technology for error detachment of measuring apparatus calibration and a highly effective algorithm for torsional vibration real-time on-line monitor of heavy-duty and complex revolving shaft.
Synchronization of a critical chaotic system with Lorenz system and Chen system
Authors: Ning Di  , Lu Jun-An  ,   武汉大学数学与统计学院，武汉  430072
Published: December 2020

A nonlinear feedback controller is designed to make the first state of a new chaotic system track an arbitrary smooth reference signal at an exponential rate. In addition, Chaos synchronization between two different chaotic systems by using active control is presented. This technique is applied to achieve chaos synchronization between the critical system, Lorenz system and Chen system. Numerical simulations are madc to verify the results.
A new scheme of suppression of spiral and spatiotemporal chaos in centric field
Authors: Ma Jun  , Pu Zhong-Sheng  , Feng Wang-Jun  , Li Wei-Xue  ,   (1)兰州理工大学物理系，兰州  730050; (2)兰州理工大学物理系，兰州  730050;浙江大学近代物理中心,杭州  310027
Published: December 2020

Suppression of spiral in centric field is investigated. The spiral is suppressed by circumrotating the system with mechanical force. It is the first time spiral is supressed and spatiotemporal chaos dispelled using this scheme. The Fitzhugh-Nagumo equation and Panfilov equation are investigated, and numerical simulation shows that the scheme is effective and robust to certain white noise.
Bifurcation of safe basins in softening Duffing oscillator under bounded noise excitation
Authors: Rong Hai-Wu  , Wang Xiang-Dong  , Xu Wei  , Fang Tong  ,   (1)佛山大学数学系，佛山  528000; (2)西北工业大学应用数学系，西安  710072
Published: December 2020

The erosion of the safe basins of a softening Duffing oscillator under harmonic or bounded random noise is studied in detail using the Monte-Carlo method. As an alternative, stochastic bifurcation may be defined as a sudden change in the character of the stochastic safe basin when the bifurcation parameter of the system passes through a critical value. This definition applies equally well either to randomly perturbed motion, or to purely deterministic motion. It is found that random noise may destroy the integrity of safe basins and bring about stochastic bifurcation, hence make the system more unsafe.
Calculation of the transition spectra of sodium atom via TDDFT
Authors: Gu Bin  , Jin Nian-Qing  , Wang Zhi-Ping  , Zeng Xiang-Hua  ,   扬州大学物理科学与技术学院，复杂性科学中心，扬州  225002
Published: December 2020

The time dependant density functional theory(TDDFT) and local density approximation (LDA) are used to calculate the transition spectra of sodium atom. Several excited energy levels of valence-electron and the corresponding electronic wave function distribution are calculated in detail. The characteristic transition Rydberg series spectra of sodium are given. The calculated results agree with the experiment data very well, which is a good evidence for the applicability of TDDFT to the description of the excited system.
Electronic structure of the surface of LaNi5 crystal
Authors: Lin Shao-Jie  , Zheng Hao-Ping  ,   同济大学玻耳固体物理研究所，上海  200092
Published: December 2020

The spin-polarized, all-electron, full-potential ab initio calculations have been performed for the electronic structure of the surface of LaNi5 crystal using the self-consistent cluster-embedding (SCCE) calculation method. The geometrical surface structure of LaNi5 crystal and its electronic structure having lowest ground-state energy are obtained, with the full relaxation of atomic positions along the direction perpendicular to the surface. On the surface of LaNi5 crystal, it is found that the La atom protruded out, and the Ni atoms caved in, so the surface becomes uneven which increases the contacting area with the hydrogen. The effective volume of the surface layer rises by 9%, which is in favour of the absorption of hydrogen. The Fermi level of the surface of LaNi5 crystal, which is made mainly of the 3d electrons of Ni,is much higher than that of body LaNi5. The valence band is not fully filled, which shows the metallic property. For the first two layers of the surface of LaNi5 crystal, there are 1.15 electrons transferred from La to Ni, and the two layers have small opposite spin magnetic moments which shows the paramagnetism. The density of state (DOS) of the valence band is obtained. The ionization potential and the electron affinity are calculated by the transition-state mathod. All calculated results show that although the properties of the surface of LaNi5 crystal are significantly different from that of body LaNi5, they are very similar to that of hydride LaNi5H7, so the structure of the surface of LaNi5 crystal is in favour of the absorption of hydrogen.
Nonparaxial propagation of Gaussian beam in arbitrary linearly polarized state
Authors: Zhou Guo-Quan  ,   浙江林学院信息物理系，浙江林学院光电子研究所，浙江临安  311300
Published: December 2020

The forming of transmitted-aperture in Sb layer of Super-RENS was studied based on laser-induced thermal model with Gauss assumption. The optical transmit model was created with optical admittance characteristic matrix. A numerical simulation was carried out by FEMLAB to understand the forming process of the aperture. The simulation results showed that transmitted aperture would not be formed until the exposure power exceeded a threshold within a certain pulse time, further more, the aperture size would be increased if the power was raised. The static writing experiment for transmitted-aperture type Super-RENS was carried out. The experiment results well agree with the simulation. It is concluded that a laser-induced thermal model could well describe the forming of aperture in Sb layer of transmitted-aperture type Super-RENS in optical data storage.
Fast tunable electro-optic polymer waveguide gratings
Authors: Wang Yi-Ping  , Chen Jian-Ping  , Li Xin-Wan  , Zhou Jun-He  , Shen Hao  , Shi Chang-Hai  , Zhang Xiao-Hong  , Hong Jian-Xun  , Ye Ai-Lun  ,   上海交通大学区域光纤通信网与新型光通信系统国家重点实验室，上海  200030
Published: December 2020

A novel fast tunable electro-optic (EO) polymer waveguide grating is proposed an d designed. Its resonant wavelength can be linearly tuned by first-order EO effe ct with a high sensitivity of 6.1pm/V. Its spectrum characteristics depend stron gly on many optical parameters of grating, such as refractive index modulation, modulation function, grating period and period number. Material selection, fabri cation technology, EO tunability and polarization dependence of the polymer wave guide grating are also discussed. This waveguide grating not only dispenses with the slow wavelength tuning and large-scale integration inconvenience of convent ional optic fiber gratings, but have many advantages, such as high resonant wave length tuning sensitivity, using same fabrication technology as semiconductor de vices, and polarization independence.
Calculation of neutron spectrum in ultraintense laser-plasmas interactions
Authors: Zhang Yi  , Li Yu-Tong  , Zhang Jie  , Chen Zheng-Lin  , Kodama R.  ,   (1)Institute of Laser Engineering,Osaka University,2-6 Yamada-oka,Suita,Osak a 565-0871,Japan; (2)中国科学院物理研究所光物理实验室，北京  100080，中国
Published: December 2020

The neutron spectrum of D-D reaction in ultraintense laser-plasma interaction is calculated. Using Maxwellian and Gauss distribution, the temperature and angular distribution of the deuterons are obtained by fitting the experimental neutron spectrum.
Experimental study of optical emission from the rear surface in ultrashort ultra-intense laser interaction with solid targets
Authors: Wang Guang-Chang  , Zheng Zhi-Jian  , Yang Xiang-Dong  , Gu Yu-Qiu  , Liu Hong-Jie  , Wen Tian-Shu  , Ge Fang-Fang  , Jiao Chun-Ye  , Zhou Wei-Min  , Zhang Shuang-Gen  , Wang Xiang-Xian  ,   (1)四川大学 原子分子物理研究所,成都  610065; (2)四川大学 原子分子物理研究所,成都  610065;中国工程物理研究院激光聚变研究中心，绵阳  621900; (3)中国工程物理研究院激光聚变研究中心，绵阳  621900
Published: December 2020

Optical emission generated by hot electrons passing through solid targets is measured from the rear surface of a metallic foil. The integrated image taken by CC D camera shows that the optical emission forms a ring, on the edge of the ring t here is a bright localized signal, which is the optical transition radiation (OT R). The optical emission spectrum shows a series of sharp nonperiodic peaks bet ween 300—500nm,obviously near 400nm(2ω). The sharp peaks are ascribed to the c oherent transition radiation (CTR) of hot electron-beam microbunching generated by v×B acceleration mechanism. The OTR intensity decreases with the increase of the target thickness.
The coherent growth and mechanical properties of non-isostructural TiN/TiB2 nanomultilayers
Authors: Wei Lun  , Mei Fang-Hua  , Shao Nan  , Dong Yun-Shan  , Li Ge-Yang  ,   上海交通大学金属基复合材料国家重点实验室，上海  200030
Published: December 2020

TiN/TiB2 nanomutlialyers with different TiB2 layer thickne ss were prepared using multi-target magnetron sputtering method. The effects of TiB2 layer thickness on the growth structure and mechanical properti es of nanomultialyers were studied by X-ray diffraction, high-resolution transmi ssion electron microscopy and nanoindentation respectively. The results reveal t hat the normally amorphous TiB2 layers crystallize in close-packed he xagonal structure when its thickness is less than 2.9 nm due to the template eff ect of cubic TiN layers. Coherent growth is found between TiN and TiB2 layers with the orientation relationship of {111}TiN//{0001}Ti B2,〈110〉TiN//〈1120〉TiB2. Because of th e lattice misfit, an alternating tensile/compressive stress field develops in th e nanomultilayers, which leads to the anomalous enhancement of hardness and elas tic modulus. Maximum hardness and elastic modulus of 46.9 and 465GPa are obtaine d at TiB2 layer thickness of 0.6nm. With increasing TiB2 l ayer thickness, amorphous TiB2 forms and blocks the coherent growth of the multilayers. Consequently, the hardness and elastic modulus of the films decrease gradually.
Defect production and formation of helium-vacancy clusters in cascades of α-iron with different concentration of helium
Authors: Yang Li  , Zu Xiao-Tao  , Xiao Hai-Yan  , Yang Shu-Zheng  , Liu Ke-Zhao  , Gao Fei  ,   (1)Pacific Northwest National Laboratory,Richland,WA 99352; (2)电子科技大学应用物理系，成都  610054; (3)电子科技大学应用物理系，成都  610054;西华师范大学物理与电子信息学院，南充  637002; (4)西华师范大学物理与电子信息学院，南充  637002; (5)中国工程物理研究院四川材料与工艺研究所，绵阳  621700
Published: December 2020

The low-temperature displacement cascades in α-Fe with different concentrations of substitutional He atoms are simulated by molecular dynamics (MD) methods. Primary knock-on atom (PKA) energy, Ep , from 500eV to 5keV is cons idered for irradiation temperature of 100K. The concentration of He in Fe varies from 1% to 5%. The results are compared with those obtained in pure α-Fe. We f ind the number of Frenkel pairs (NF) in Fe with low concentration of He atoms is nearly equal to those in pure Fe, but increases with increasing He c oncentration. The present study demonstrates for the first time that He-vacancy bubbles can be nucleated directly from displacement cascades, even at low tempe rature at which the vacancies are not mobile. However, the efficiency of He-vaca ncy clusters increases with increasing the concentration of He for the same ener gy recoils, and increases with increasing Ep for the same concentrati on of He. The mechanisms of He bubble nucleation in displacement cascades are di scussed in detail.
Effect of high temperature rapid thermal annealing on flow pattern defects in heavily Sb-doped CZSi
Authors: Hao Qiu-Yan  , Liu Cai-Chi  , Sun Wei-Zhong  , Zhang Jian-Qiang  , Sun Shi-Long  , Zhao Li-Wei  , Zhang Jian-Feng  , Zhou Qi-Gang  , Wang Jing  ,   (1)北京有色金属研究总院，北京  100088; (2)河北工业大学信息功能材料研究所，天津  300130; (3)天津大学电信学院，天津  300072;河北工业大学信息功能材料研究所，天津  300130
Published: December 2020

Flow pattern defects(FPDs) in as-grown and rapid thermal annealed heavily Sb-dop ed silicon wafers was investigated. The experimental results show that the dens ity of FPDs can be reduced after high temperature annealing, and H2 is the most effective annealing atmosphere. The mechanism of elimination of FPDs is also discussed from the relationship between heavily doping Sb and interstit ial oxygen concentration. The heavily doping Sb influences not only the distribu tion of initial oxygen concentration in CZSi wafer, but also the formation and h eat behavior of grown-in void defects.
Fabrication of intrinsic microcrystalline silicon thin films used for solar cells and its structure
Authors: Zhang Xiao-Dan  , Zhao Ying  , Gao Yang-Tao  , Zhu Feng  , Wei Chang-Chun  , Sun Jian  , Geng Xin-Hua  , Xiong Shao-Zhen  ,   (1)（南开大学光电子薄膜器件与技术研究所，天津  300071）；（南开大学光电子薄膜器件与技术天津市重点实验室，天津  300071）；(光电信息技术科学教育部重点实验室（南开大学），天津  300071); (2)南开大学光电子薄膜器件与技术研究所，天津  300071；南开大学光电子薄膜器件与技术天津市重点实验室，天津  300071；光电信息技术科学教育部重点实验室（南开大学），天津  300071
Published: December 2020

Microcrystalline silicon thin films used for solar cells were deposited at different silane concentrations and reaction pressures by VHF-PECVD.Study of materials structure was conducted by Raman spectra and x-ray diffraction. In the range of experiment, microcrystalline silicon thin films prepared under different cond itions all have (220) preferential orientation. Microcrystalline silicon solar c ells with conversion efficiency up to 7.1% were fabricated. The structure of sol ar cells was glass/ZnO/p(μc-Si:H)/i(μc-Si:H)/n(a-Si:H/Al). There was no Zno ba ck reflector and the thickness of solar cells was only 1.2μm.
Theoretical study of influence of substrate microdefects on optical properties of dielectric thin films
Authors: Shen Jian  , Liu Shou-Hua  , Shen Zi-Cai  , Kong Wei-Jin  , Huang Jian-Bing  , Shao Jian-Da  , Fan Zheng-Xiu  ,   (1)陕西科技大学材料科学与工程学院,咸阳  712081; (2)中国科学院上海光学精密机械研究所,上海  201800; (3)中国科学院上海光学精密机械研究所,上海  201800;中国科学院研究生院,北京  100039
Published: December 2020

Based on the theory of inhomogeneous thin films, a model for refractive index of stratified dielectric substrate is firstly put forward. The substrate can be divided into surface layer, subsurface layer and bulk layer in turn. Both the s urface layer and subsurface layer, whose refractive indices obey statistical dis tributions, are equivalent to inhomogeneous thin films. They can be separated in to N1 and N2 sublayers respetively which are regarded as homogenous thin films. Subsequently, theoretical analysis was carried out utili zing the characteristic matrix method of optical thin films. Numerical calculati on for optical properties of single layer dielectric thin films was carried out. The computing results indicate that microdefects in surface layer and subsurfac e layer of the substrate alter the equivalent refractive indices of the thin film and the substrate, which leads to the deviation of pseudo-Brewster angles and assembling reflectance from ideal conditions. Meanwhile, these microdefects change the propagation characteristics in thin film and substrate, as a result t he phase shift of reflection and phase difference deviate from ideal conditions. In addition, this model is also suitable for calculating the influence of micr odefects in the substrate on optical propertied of multilayer dielectric thin fi lms.
Investigation of diamond-like-carbon films prepared by unbalanced magnetron sputtering
Authors: Yang Wu-Bao  , Fan Song-Hua  , Zhang Gu-Ling  , Ma Pei-Ning  , Zhang  Shou-Zhong  , Du Jian  ,   (1)北京丹普表面技术公司,北京  100096; (2)石油大学（北京）机电工程学院,北京  102249; (3)石油大学（北京）机电工程学院,北京  102249;北京丹普表面技术公司,北京  100096; (4)中国科学院物理研究所,北京  100080
Published: December 2020

Using unbalanced magnetron sputtering method, smooth, dense and uniform diamond like carbon films (DLC) with high diamond phase content are deposited.Based on testing and analysis of deposition mechanism, we conclude that with smaller s puttering clusters and higher collision frequency between the sputtering cluster and environment molecules, and more suitable momentum of the sputtering cluste r impacting on the substrate, higher content of diamond phase in the film will result. Scanning electron micrograph shows that there are no obvious grains in this film. The micro-hardness is about 11 GPa, bulk elastic modulus is about 120 GPa as tested by nano-indentation. The optical transmittance is about 89%, ref raction coefficient is 1.952, and the deposition rate is 0.724μm/h as calculate d from the FTIR spectra.
Fragmentation in DNA double-strand breaks
Authors: Wei Zhi-Yong  , Zang Li-Hui  , Li Ming  , Fan Wo  , Xu Yu-Jie  ,   (1)南京航空航天大学材料科学与技术学院医学物理系，南京  210016;苏州大学放射医学与公共卫生学院，苏州  215007; (2)苏州大学放射医学与公共卫生学院，苏州  215007
Published: December 2020

DNA double strand breaks are important lesions induced by irradiations. Random breakage model or quantification supported by this concept is suitable to analyze DNA double strand break data induced by low LET radiation,but deviation from random breakage model is more evident in high LET radiation data analysis. In this work we develop a new method , statistical fragmentation model , to analyze the fragmentation process of DNA double strand breaks. After charged particles enter the biological cell, they produce ionizations along their tracks, and transfer their energies to the cells and break the cellular DNA strands into fragments. The probable distribution of the fragments is obtained under the condition in wh ich the entropy is maximum. Under the approximation E≈E0+E1l+E2l2, the distribution functions are obtained as exp( αl+βl2) . There are two components, the one proportional to exp(βl2)，mainly contributes to the low mass fragment yields, the other comp onent, proportional to exp(αl)，decreases slowly as the mass of the fragments i ncreases. Numerical solution of the constraint equations provides parameters α and β. Experimental data , especially when the energy deposition is higher, sup port the statistical fragmentation model.
Effect of pre-pulses on capillary discharge soft x-ray laser
Authors: Cheng Yuan-Li  , Luan Bo-Han  , Wu Yin-Chu  , Zhao Yong-Peng  , Wang Qi  , Zheng  Wu-Di  , Peng Hui-Min  , Yang Da-Wei  ,   (1)北京应用物理与计算数学研究所，北京  100088; (2)哈尔滨工业大学可调谐激光技术国家级重点实验室，哈尔滨  150001; (3)中国原子能科学研究院，北京  102413
Published: December 2020

On a capillary discharge setup lasing in Ne-like Ar at 46.9nm, the ablation of c apillary wall was investigated for polythene and alumina material at both of inh erent 2—5kA-pre-pulse of setup and separate pre-pulse of 20A by measuring soft x ray emission from the capillary discharged. For inherent pre-pulse and polythe ne capillary, the ablation is too large to create uniform plasma columns and it is impossible to obtain lasing. In the case of 20A-pre-pulse and alumina capilla ry, the ablation decreased remarkably and the laser spike pulse was distinguishe d on an x-ray diode because the uniform Z-Pinch plasma column had formed.
New solitary wave-like solution and exact solution of variable coefficient KP equation
Authors: Mao Jie-Jian  , Yang Jian-Rong  ,   江西上饶师范学院物理系，上饶  334001
Published: December 2020

With the help of the general Sine-Gordon travelling wave transformation equation, we present a new method for solving the variable coefficient KP equation, and successfully obtain the new solitary wave-like solution, the Jacobi elliptic function-like solution and trigonometric function solution of variable coefficient KP equation.
A quantum key distribution system based on two polarization beam splitters
Authors: Ma Hai-Qiang  , Li Ya-Ling  , Zhao Huan  , Wu Ling-An  ,   (1)中国科学院物理研究所光物理开放实验室, 北京  100080; (2)中国科学院物理研究所光物理开放实验室, 北京  100080;北京交通大学,  北京  100044; (3)中国科学院物理研究所光物理开放实验室, 北京  100080;东南大学, 南京  210096
Published: December 2020

We present a quantum key distribution system based on two polarization beam splitters, by means of which the phase modulator's polarization dependence is cancelled out. A high key generation rate has been obtained for the first time at 1310nm transmitted over a 25 km long fiber, with a fringe visibility of 99.4%. A sifted key rate of about 0.6 kbits/s and quantum bit error rate of about 0.5% are obtained.
Controlling chaos using time-delay nonlinear feedback
Authors: Yu Hong-Jie  ,   上海交通大学工程力学系，上海  200240
Published: December 2020

A method of chaos control using time-delay nonlinear feedback based on stability criterion is proposed. By a suitable separation of the chaotic system, a special nonlinear function is obtained. We use the difference of nonlinear functions of the chaotic output signal and its delayed output signal to construct a continuous feedback input perturbation. The method can stabilize chaotic systems to a desired periodic orbit without using any external force. The method retains the advantages of performing the self-control via delayed feedback control method. Besides, the validity of control is ensured due to the stability criterion. The control can be started at any moment, and it is convenient and flexible. The coupled Duffing oscillator is given as numerical examples. The results of numerical simulation show the validity of the method.
Speed feedback synchronization of a chaotic system
Authors: Tao Chao-Hai  , Lu Jun-An  ,   (1)武汉大学数学与统计学院，武汉  430072; (2)重庆邮电学院计算机科学与技术学院，重庆  400065
Published: December 2020

The speed feedback synchronization of a chaotic system has been studied by using linear feedback synchronization, generalized synchronization and coupled synchronization methods. The coefficients of speed feedback synchronization have been figured out and are smaller than those of the general feedback synchronization, so the complexity and cost is reduced. Numerical simulations show the effectiveness of the methods.
Calculation of helium 1D—3D term intervals for　1snd(n=4—11) states
Authors: He Li-Ming  , Cao Wei  , Chen Xue-Qian  , Zhu Yun-Xia  ,   华东理工大学物理系，上海  200237
Published: December 2020

With many-body perturbation theory (MBPT), 1D—3D term intervals of helium　1snd(n=4—11) configurations have been calculated. Based on two different models, Rayleigh-Schrdinger perturbation expansion terms only consisting of bound states and those of continua are calculated respectively. For bound states, the zeroth-order wave functions are strictly generated from self-iteration solutions of Hartree equation and residues of infinite perturbation series are dealt with by integral processing method. For continuum parts, a simplified hydrogen potential model is adopted. According to Rayleigh-Schrdinger expansion, the perturbation corrections to Rydberg states have been evaluated up to the third-order terms. From the calculation, the energy splittings are mainly attributed to bound parts. Singlet-triplet level splittings yielded here are found to agree quite well with two sets of experimental results.