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The(1+1)-dimensional nonlinear ion acoustic waves in multicomponent plasma containing kappa electrons
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作者 林麦麦 蒋蕾 王明月 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第12期416-421,共6页
Large amplitude (1+1)-dimensional nonlinear ion acoustic waves are theoretically studied in multicomponent plasma consisting of positively charged ions and negatively charged ions, ion beam, kappa-distributed electron... Large amplitude (1+1)-dimensional nonlinear ion acoustic waves are theoretically studied in multicomponent plasma consisting of positively charged ions and negatively charged ions, ion beam, kappa-distributed electrons, and dust grains,respectively. By using the Sagdeev potential method, the dynamical system and the Sagdeev potential function are obtained.The important influences of system parameters on the phase diagram of this system are investigated. It is found that the linear waves, the nonlinear waves and the solitary waves are coexistent in the multicomponent plasma system. Meanwhile,the variations of Sagdeev potential with parameter can also be obtained. Finally, it seems that the propagating characteristics of (1+1)-dimensional nonlinear ion acoustic solitary waves and ion acoustic nonlinear shock wave can be influenced by different parameters of this system. 展开更多
关键词 multicomponent plasma nonlinear ion acoustic waves Sagdeev potential method
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Theoretical and Experimental Study on the Acoustic Wave Energy After the Nonlinear Interaction of Acoustic Waves in Aqueous Media 被引量:1
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作者 兰朝凤 李凤臣 +3 位作者 陈欢 卢迪 杨德森 张梦 《China Ocean Engineering》 SCIE EI CSCD 2015年第4期611-621,共11页
Based on the Burgers equation and Manley-Rowe equation, the derivation about nonlinear interaction of the acoustic waves has been done in this paper. After nonlinear interaction among the low-frequency weak waves and ... Based on the Burgers equation and Manley-Rowe equation, the derivation about nonlinear interaction of the acoustic waves has been done in this paper. After nonlinear interaction among the low-frequency weak waves and the pump wave, the analytical solutions of acoustic waves' amplitude in the field are deduced. The relationship between normalized energy of high-frequency and the change of acoustic energy before and after the nonlinear interaction of the acoustic waves is analyzed. The experimental results about the changes of the acoustic energy are presented. The study shows that new frequencies are generated and the energies of the low-frequency are modulated in a long term by the pump waves, which leads the energies of the low-frequency acoustic waves to change in the pulse trend in the process of the nonlinear interaction of the acoustic waves. The increase and decrease of the energies of the low-frequency are observed under certain typical conditions, which lays a foundation for practical engineering applications. 展开更多
关键词 nonlinear interaction amplitude solution of the acoustic waves energy amplification of low-frequencyacoustic waves energy reduction of low-frequency acoustic waves
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PROPAGATION OF SURFACE ACOUSTIC WAVES IN PRESTRESSED ANISOTROPIC LAYERED PIEZOELECTRIC STRUCTURES 被引量:5
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作者 Liu Hua Kuang Zhenbang +2 位作者 Cai Zhengming Wang Tiejun Wang Zikun 《Acta Mechanica Solida Sinica》 SCIE EI 2003年第1期16-23,共8页
The propagation of surface acoustic waves in layered piezoelectric structureswith initial stresses is investigated. The phase velocity equations are obtained for electricallyfree and shorted cases, respectively. Effec... The propagation of surface acoustic waves in layered piezoelectric structureswith initial stresses is investigated. The phase velocity equations are obtained for electricallyfree and shorted cases, respectively. Effects of the initial stresses on the phase velocity and theelectromechanical coupling coefficient for the fundamental mode of the layered piezoelectricstructures are discussed. Numerical results for the c-axis oriented film of LiNbO_3 on a sapphiresubstrate are given. It is found that the fractional change in phase velocity is a linear functionwith the initial stresses, and the electromechanical coupling factor increases with an increase ofthe absolute values of the compressive initial stresses. The results are useful for the design ofsurface acoustic wave devices. 展开更多
关键词 surface acoustic waves layered piezoelectric structure phase velocity electromechanical coupling coefficient
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Nondestructive determination of film thickness with laser-induced surface acoustic waves 被引量:1
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作者 Xia Xiao Tao Kong +1 位作者 Hai Yang Qi and Hui Quan Qing 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第9期457-461,共5页
The application of surface acoustic waves(SAWs) for thickness measurement is presented. By studying the impact of film thickness h on the dispersion phenomenon of surface acoustic waves, a method for thickness deter... The application of surface acoustic waves(SAWs) for thickness measurement is presented. By studying the impact of film thickness h on the dispersion phenomenon of surface acoustic waves, a method for thickness determination based on theoretical dispersion curve v( fh) and experimental dispersion curve v( f) is developed. The method provides a series of thickness values at different frequencies f, and the mean value is considered as the final result of the measurement. The thicknesses of six interconnect films are determined by SAWs, and the results are compared with the manufacturer's data.The relative differences are in the range from 0.4% to 2.18%, which indicates that the surface acoustic wave technique is reliable and accurate in the nondestructive thickness determination for films. This method can be generally used for fast and direct determination of film thickness. 展开更多
关键词 thickness measurement dispersion curve surface acoustic waves layered structure
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Manipulating Backward Propagation of Acoustic Waves by a Periodical Structure
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作者 徐峥 钱梦騄 +1 位作者 程茜 刘晓峻 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第11期58-61,共4页
In the backward propagation of acoustic waves, the direction of phase velocity is anti-parallel to that of group velocity. We propose a scheme to manipulate the backward propagation using a periodicM structure. The dy... In the backward propagation of acoustic waves, the direction of phase velocity is anti-parallel to that of group velocity. We propose a scheme to manipulate the backward propagation using a periodicM structure. The dynamic backward propagation process is further experimentally observed. It is demonstrated that the oblique incident plane wave moves backward when it travels through the periodical structure and the backward shift can be controlled within a certain range. 展开更多
关键词 of on AS Manipulating Backward Propagation of acoustic waves by a Periodical Structure IS by MHZ into
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Breath monitoring,sleep disorder detection,and tracking using thin-film acoustic waves and open-source electronics
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作者 Jethro Vernon Pep Canyelles-Pericas +4 位作者 Hamdi Torun Richard Binns Wai Pang Ng Qiang Wu Yong-Qing Fu 《Nanotechnology and Precision Engineering》 CAS CSCD 2022年第3期9-17,共9页
Apnoea,a major sleep disorder,affects many adults and causes several issues,such as fatigue,high blood pressure,liver conditions,increased risk of type II diabetes,and heart problems.Therefore,advanced monitoring and ... Apnoea,a major sleep disorder,affects many adults and causes several issues,such as fatigue,high blood pressure,liver conditions,increased risk of type II diabetes,and heart problems.Therefore,advanced monitoring and diagnosing tools of apnoea disorders are needed to facilitate better treatment,with advantages such as accuracy,comfort of use,cost effectiveness,and embedded computation capabilities to recognise,store,process,and transmit time series data.In this work we present an adaptation of our apnoea-Pi open-source surface acoustic wave(SAW)platform(Apnoea-Pi)to monitor and recognise apnoea in patients.The platform is based on a thin-film SAW device using bimorph ZnO and Al structures,including those fabricated as Al foils or plates,to achieve breath tracking based on humidity and temperature changes.We applied open-source electronics and provided embedded computing characteristics for signal processing,data recognition,storage,and transmission of breath signals.We show that the thin-film SAW device out-performed standard and off-the-shelf capacitive electronic sensors in terms of their response and accuracy for human breath-tracking purposes.This in combination with embedded electronics makes a suitable platform for human breath monitoring and sleep disorder recognition. 展开更多
关键词 Surface acoustic waves Sleep disorder APNOEA Open-source electronics Pattern recognition Piezoelectric thin film
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Analytical Study of Nonlinear Dust Acoustic Waves in Two-Dimensional Dust Plasma with Dust Charge Variation
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作者 LIN Chang ZHANG Xiu-Lian 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第2X期247-251,共5页
The nonlinear dust acoustic waves in two-dimensional dust plasma with dust charge variation is analytically investigated by using the formally variable separation approach. New analytical solutions for the governing e... The nonlinear dust acoustic waves in two-dimensional dust plasma with dust charge variation is analytically investigated by using the formally variable separation approach. New analytical solutions for the governing equation of this system have been obtained for dust acoustic waves in a dust plasma for the first time. We derive exact analytical expressions for the general case of the nonlinear dust acoustic waves in two-dimensional dust plasma with dust charge variation. 展开更多
关键词 nonlinear dust acoustic waves plasma formally variable separation approach exact analytical solution
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Nonlinear acoustic waves in a collisional self-gravitating dusty plasma
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作者 郭志荣 杨增强 +1 位作者 殷保祥 孙茂珠 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第11期489-493,共5页
Using the reductive perturbation method, we investigate the small amplitude nonlinear acoustic wave in a collisional self-gravitating dusty plasma. The result shows that the small amplitude dust acoustic wave can be e... Using the reductive perturbation method, we investigate the small amplitude nonlinear acoustic wave in a collisional self-gravitating dusty plasma. The result shows that the small amplitude dust acoustic wave can be expressed by a modified Korteweg-de Vries equation, and the nonlinear wave is instable because of the collisions between the neutral gas molecules and the charged particles. 展开更多
关键词 nonlinear acoustic waves collisional self-gravitating dusty plasma modified Korteweg de Vries equation INSTABILITY
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The Propagation, Excitation and Coupling of Acoustic Waves in Phonon Band-gap Materials
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作者 CHEN Yan-feng ZHU Yong-yuan +1 位作者 ZHU Shi-ning MING Nai-ben 《四川大学学报(自然科学版)》 CAS CSCD 北大核心 2005年第S1期24-24,共1页
Acoustic wave exhibits inherently different characters of propagation, excitation and coupling in phonon band-gap materials in which its elastic, piezoelectric constants are modulated in order of acoustic wavelength. ... Acoustic wave exhibits inherently different characters of propagation, excitation and coupling in phonon band-gap materials in which its elastic, piezoelectric constants are modulated in order of acoustic wavelength. These kinds of novel materials were exampled by phononic crystals with elastic constants modulation, acoustic superlattice and ionic-type phononic crystals with piezoelectric constants modulation. In this talk, phonic crystals were constructed with steel rods embedded in air. Negative refraction of acoustic wave was both experimentally and theoretically established in the phononic crystals. The propagation of acoustic wave in the crystals show acoustic band structures because the waves are strong scattered at the Brillouin Zone Boundaries, analogy to electron band structure in real crystals and photonic band structure in photonic crystals. In the acoustic superlattice, ultrasonic waves could be excited by applied alternative electric fields by piezoelectric effect. The frequency, mode and amplitude of the excited wave are determined by the microstructured parameters of the acoustic superlattice at the condition of phase matching. Ionic-type phononic crystals describe the coupling between superlattice phonon and electromagnetic wave. The coupling process resulted in the polariton with a dispersion relation totally different from that of both superlattice phonon and E-M waves, analogy to the polariton of the ionic crystals but in microwave instead of infrared light. These microstructural dielectric materials show artificial abnormal properties and will find novel application in ultrasonic devices and microwave devices. 展开更多
关键词 REV PING The Propagation Excitation and Coupling of acoustic waves in Phonon Band-gap Materials
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Relativistic degenerate effects of electrons and positrons on modulational instability of quantum ion acoustic waves in dense plasmas with two polarity ions
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作者 刘铁路 王云良 路彦珍 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第2期295-301,共7页
The nonlinear propagation of quantum ion acoustic wave(QIAW) is investigated in a four-component plasma composed of warm classical positive ions and negative ions,as well as inertialess relativistically degenerate e... The nonlinear propagation of quantum ion acoustic wave(QIAW) is investigated in a four-component plasma composed of warm classical positive ions and negative ions,as well as inertialess relativistically degenerate electrons and positrons.A nonlinear Schrodinger equation is derived by using the reductive perturbation method,which governs the dynamics of QIAW packets.The modulation instability analysis of QIAWs is considered based on the typical parameters of the white dwarf.The results exhibit that both in the weakly relativistic limit and in the ultrarelativistic limit,the modulational instability regions are sensitively dependent on the ratios of temperature and number density of negative ions to those of positive ions respectively,and on the relativistically degenerate effect as well. 展开更多
关键词 quantum ion acoustic waves modulational instability relativistic degenerate
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Propagation Characteristics of Surface Acoustic Waves on LGT and Quartz Substrates
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作者 张国伟 卢秋红 《Journal of Donghua University(English Edition)》 EI CAS 2014年第2期160-164,共5页
Langatate( LGT) is a novel piezoelectric crystal; its structure is similar to quartz. A numerical analysis of the most important propagation characteristics of surface acoustic waves( SAW) on LGT and quartz is present... Langatate( LGT) is a novel piezoelectric crystal; its structure is similar to quartz. A numerical analysis of the most important propagation characteristics of surface acoustic waves( SAW) on LGT and quartz is presented in this paper. The results show that the phase velocity on LGT is slower than that on quartz.Similar to quartz,there are zero temperature cuts and pure module orientations on LGT. The electro-mechanical coupling constant( k2)of LGT is larger than that of quartz. The characteristics of SAW on LGT with different material constants are calculated and compared.The results show that there are somewhat deviations with different material constants. Especially, the temperature coefficient of frequency( TCF) shows a relatively high difference. 展开更多
关键词 Langatate(LGT) QUARTZ surface acoustic waves(SAW)
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The Pulsed Plasma-Liquid Systems at Cylindrical Geometry with Possibility of Convergent Acoustic Waves Efficient Generation
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作者 Valeriy Chernyak Sergiy Sidoruk +5 位作者 Vitaliy Yukhymenko Eugen Martysh Oleg Nedybaliuk OlegFedorovich Ida Babich Tamara Lisitchenko 《Journal of Chemistry and Chemical Engineering》 2012年第8期753-759,共7页
This research investigates the possibility of convergent acoustic waves generation in the liquid by means of the sotmd waves reflection from the solid cylindrical surface, emerged in the pulsed electric discharge. The... This research investigates the possibility of convergent acoustic waves generation in the liquid by means of the sotmd waves reflection from the solid cylindrical surface, emerged in the pulsed electric discharge. The spectra of pulse discharge plasma emission in the water and in the air-water mixture were obtained. The temperature of cuprum and oxygen atoms electronic excitation levels and the temperature tendencies during the discharge current existence were calculated. 展开更多
关键词 Pulsed plasma-liquid system convergent acoustic waves non-ideal plasma temperature.
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SOME PROPERTIES OF FAR FIELD PATTERNS OF ACOUSTIC WAVES IN AN INHOMOGENEOUS MEDIUM
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作者 程晋 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1990年第8期787-793,共7页
In this paper, by using functional analysis and integral equation method, we obtain some results about the properties of far field of acoustic waves in an inhomogeneous medium. And we also discuss some ill-posed inver... In this paper, by using functional analysis and integral equation method, we obtain some results about the properties of far field of acoustic waves in an inhomogeneous medium. And we also discuss some ill-posed inverse scattering problems by Tikhonov regularization method. 展开更多
关键词 SOME PROPERTIES OF FAR FIELD PATTERNS OF acoustic waves IN AN INHOMOGENEOUS MEDIUM
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Influence of Viscosity in Fluid Atomization with Surface Acoustic Waves
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作者 Andreas Winkler Paul Bergelt +1 位作者 Lars Hillemann Siegfried Menzel 《Open Journal of Acoustics》 2016年第3期23-33,共11页
In this work, aqueous glycerol solutions are atomized to investigate the influence of the viscosity on the droplet size and the general atomization behavior in a setup using standing surface acoustic waves (sSAW) and ... In this work, aqueous glycerol solutions are atomized to investigate the influence of the viscosity on the droplet size and the general atomization behavior in a setup using standing surface acoustic waves (sSAW) and a fluid supply at the boundary of the acoustic path. Depending on the fluid viscosity, the produced aerosols have a monomodal or polymodal size distribution. The mean droplet size in the dominant droplet fraction, however, decreases with increasing viscosity. Our results also indicate that the local wavefield conditions are crucial for the atomization process. 展开更多
关键词 Surface acoustic waves ATOMIZATION AEROSOL High Viscosity Droplet Size Distribution Wavefield
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Temperature Characteristics of Surface Acoustic Waves Propagating on La_3Ga_5SiO_4 Substrates 被引量:2
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作者 Guowei ZHANG, Wenkang SHI, Xiaojun JI, Tao HAN, Feng DU and Lianger LISchool of Electronics & Information, Shanghai Jiao Tong University, Shanghai 200030, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2004年第1期63-66,共4页
Langasite (LGS) is a novel piezoelectric crystal. The authors numerically analyses the temperature stability of surface acoustic waves (SAW) and the relation of SAW propagation with temperature on certain optimal cuts... Langasite (LGS) is a novel piezoelectric crystal. The authors numerically analyses the temperature stability of surface acoustic waves (SAW) and the relation of SAW propagation with temperature on certain optimal cuts on LGS in this paper. The results show that LGS has better temperature stability than traditional piezo crystals. The results also demonstrate that the velocity of SAW decrease with temperature, the electro-mechanical coupling constant (k2) and temperature coefficient of frequency increases parabolically and the power flow angle increases linearly on certain optimal cuts of LGS. The calculation result compared with the experimental and show good agreement. 展开更多
关键词 La3Ga5SiO4 (LGS) Surface acoustic wave (SAW) Temperature characteristic
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Influence of roughness on the detection of mechanical characteristics of low-k film by the surface acoustic waves
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作者 肖夏 陶冶 孙远 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第10期424-428,共5页
The surface acoustic wave (SAW) technique is a precise and nondestructive method to detect the mechanical charac- teristics of the thin low dielectric constant (low-k) film by matching the theoretical dispersion c... The surface acoustic wave (SAW) technique is a precise and nondestructive method to detect the mechanical charac- teristics of the thin low dielectric constant (low-k) film by matching the theoretical dispersion curve with the experimental dispersion curve. In this paper, the influence of sample roughness on the precision of SAW mechanical detection is inves- tigated in detail. Random roughness values at the surface of low-k film and at the interface between this low-k film and the substrate are obtained by the Monte Carlo method. The dispersive characteristic of SAW on the layered structure with rough surface and rough interface is modeled by numerical simulation of finite element method. The Young's moduli of the Black DiamondTM samples with different roughness values are determined by SAWs in the experiment. The results show that the influence of sample roughness is very small when the root-mean-square (RMS) of roughness is smaller than 50 nm and correlation length is smaller than 20 μm. This study indicates that the SAW technique is reliable and precise in the nondestructive mechanical detection for low-k films. 展开更多
关键词 low-k film mechanical character detection rough surface rough interface surface acoustic wave
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Oblique collisional effects of dust acoustic waves in unmagnetized dusty plasma
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作者 M S Alam M R Talukder 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第6期304-313,共10页
Effects of oblique collisions of the dust acoustic(DA)waves in dusty plasma are studied by considering unmagnetized fully ionized plasma.The plasma consists of inertial warm negatively charged massive dusts,positively... Effects of oblique collisions of the dust acoustic(DA)waves in dusty plasma are studied by considering unmagnetized fully ionized plasma.The plasma consists of inertial warm negatively charged massive dusts,positively charged dusts,superthermal kappa distributed electrons,and isothermal ions.The extended Poincaré–Lighthill–Kuo(e PLK)method is employed for the drivation of two-sided Korteweg–de Vries(KdV)equations(KdVEs).The Kd V soliton solutions are derived by using the hyperbolic secant method.The effects of superthermality index of electrons,temperature ratio of isothermal ion to electron,and the density ratio of isothermal ions to negatively charged massive dusts on nonlinear coefficients are investigated.The effects of oblique collision on amplitude,phase shift,and potential profile of right traveling solitons of DA waves are also studied.The study reveals that the new nonlinear wave structures are produced in the colliding region due to head-on collision of the two counter propagating DA waves.The nonlinearity is found to decrease with the increasing density ratio of ion to negative dust in the critical region.The phase shifts decrease(increase)with increasing the temperature ratio of ion to electron(κe).The hump(compressive,κe<κec)and dipshaped(rarefactive,κe>κec)solitons are produced depending on the angle(θ)of oblique collision between the two waves. 展开更多
关键词 ion acoustic wave dusty plasma kappa distribution ePLK method hyperbolic secant method
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Dust acoustic waves in collisional uniform dense magnetoplasma
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作者 Jian-Rong Yang Ting Xu +2 位作者 Jie-Jian Mao Ping Liu Xi-Zhong Liu 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第1期298-303,共6页
In order to study the characteristics of dust acoustic waves in a uniform dense dusty magnetoplasma system, a nonlinear dynamical equation is deduced using the quantum hydrodynamic model to account for dust–neutral c... In order to study the characteristics of dust acoustic waves in a uniform dense dusty magnetoplasma system, a nonlinear dynamical equation is deduced using the quantum hydrodynamic model to account for dust–neutral collisions. The linear dispersion relation indicates that the scale lengths of the system are revised by the quantum parameter, and that the wave motion decays gradually leading the system to a stable state eventually. The variations of the dispersion frequency with the dust concentration, collision frequency, and magnetic field strength are discussed. For the coherent nonlinear dust acoustic waves, new analytic solutions are obtained, and it is found that big shock waves and wide explosive waves may be easily produced in the background of high dusty density, strong magnetic field, and weak collision. The relevance of the obtained results is referred to dense dusty astrophysical circumstances. 展开更多
关键词 dusty magnetoplasma quantum hydrodynamic model dust acoustic wave
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Nonlinear Dust Acoustic Waves in a Magnetized Dusty Plasma with Trapped and Superthermal Electrons
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作者 S.Ahmadi ABRISHAMI M.Nouri KADIJANI 《Plasma Science and Technology》 SCIE EI CAS CSCD 2014年第6期545-551,共7页
In this work, the effects of superthermal and trapped electrons on the oblique propa- gation of nonlinear dust-acoustic waves in a magnetized dusty (complex) plasma are investigated. The dynamic of electrons is simu... In this work, the effects of superthermal and trapped electrons on the oblique propa- gation of nonlinear dust-acoustic waves in a magnetized dusty (complex) plasma are investigated. The dynamic of electrons is simulated by the generalized Lorentzian (k) distribution function (DF). The dust grains are cold and their dynamics are simulated by hydrodynamic equations. Using the standard reductive perturbation technique (RPT) a nonlinear modified Korteweg-de Vries (mKdV) equation is derived. Two types of solitary waves; fast and slow dust acoustic solitons, exist in this plasma. Calculations reveal that compressive solitary structures are likely to propagate in this plasma where dust grains are negatively (or positively) charged. The properties of dust acoustic solitons (DASs) are also investigated numerically. 展开更多
关键词 dust acoustic wave trapped electrons superthermal electrons kappa distribution function
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Topological charge pump by surface acoustic waves
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作者 郑一 冯世平 杨师杰 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第6期468-473,共6页
Quantized electron pumping by the surface acoustic wave across barriers created by a sequence of split metal gates is interpreted from the viewpoint of topology.The surface acoustic wave serves as a one-dimensional pe... Quantized electron pumping by the surface acoustic wave across barriers created by a sequence of split metal gates is interpreted from the viewpoint of topology.The surface acoustic wave serves as a one-dimensional periodical potential whose energy spectrum possesses the Bloch band structure.The time-dependent phase plays the role of an adiabatic parameter of the Hamiltonian which induces a geometrical phase.The pumping currents are related to the Chern numbers of the filled bands below the Fermi energy.Based on this understanding,we predict a novel effect of quantized but nonmonotonous current plateaus simultaneously pumped by two homodromous surface acoustic waves. 展开更多
关键词 quantized pumping surface acoustic wave topological band structure
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