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Explanation of Relation between Wave Function and Probability Density Based on Quantum Mechanics in Phase Space
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作者 Chol Jong Jin-Sim Kim +1 位作者 Shin-Hyok Jon Son-Il Jo 《World Journal of Mechanics》 2023年第1期20-72,共53页
The main problem of quantum mechanics is to elucidate why the probability density is the modulus square of wave function. For the purpose of solving this problem, we explored the possibility of deducing the fundamenta... The main problem of quantum mechanics is to elucidate why the probability density is the modulus square of wave function. For the purpose of solving this problem, we explored the possibility of deducing the fundamental equation of quantum mechanics by starting with the probability density. To do so, it is necessary to formulate a new theory of quantum mechanics distinguished from the previous ones. Our investigation shows that it is possible to construct quantum mechanics in phase space as an alternative autonomous formulation and such a possibility enables us to study quantum mechanics by starting with the probability density rather than the wave function. This direction of research is contrary to configuration-space formulation of quantum mechanics starting with the wave function. Our work leads to a full understanding of the wave function as the both mathematically and physically sufficient representation of quantum-mechanical state which supplements information on quantum state given solely by the probability density with phase information on quantum state. The final result of our work is that quantum mechanics in phase space satisfactorily elucidates the relation between the wave function and the probability density by using the consistent procedure starting with the probability density, thus corroborating the ontological interpretation of the wave function and withdrawing a main assumption of quantum mechanics. 展开更多
关键词 Quantum Ensemble Theory Quantum Mechanics In Phase space wave Function Probability Density Schrödinger Equation
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On Scalar Planck Waves
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作者 Lewis Nash 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第4期1551-1563,共13页
The sound of space-time at the large scale is observed in the form of gravitational waves, which are disturbances in space-time produced by wavelike distortions (or kinks) in the gravitational field of an accelerating... The sound of space-time at the large scale is observed in the form of gravitational waves, which are disturbances in space-time produced by wavelike distortions (or kinks) in the gravitational field of an accelerating parcel or distribution of energy. In this study, we investigate a hypothetical wave mode of quantum space-time, which suggests the existence of scalar Planck waves. According to this hypothesis, the sound of quantum space-time corresponds to kinks propagating in the gravitational displacement field of an oscillating energy density. In evaluating the emission of scalar Planck waves and their effect on the geometry of space-time, one finds that they not only transport a vanishingly small amount of energy but can also be used to simulate gravity. 展开更多
关键词 Scalar Planck waves Quantum space-Time Dynamics Gravitational waves Gravitational Displacement Field Artificial Gravity
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Some Aspects of Ray Representation Running Sound Waves in Liquid Spaces 被引量:2
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作者 V. P. Ivanov G. K. Ivanova 《Open Journal of Acoustics》 2013年第1期7-13,共7页
Work is devoted to the analysis of errors meeting in literature in treatment of a spatial part of a phase of running sound waves. In some cases, it is not taken into consideration that this part of a phase is formed b... Work is devoted to the analysis of errors meeting in literature in treatment of a spatial part of a phase of running sound waves. In some cases, it is not taken into consideration that this part of a phase is formed by scalar product of vectors which does not depend on a choice of system of co-ordinates. Taking into account the necessary corrections in record of a phase of plane waves, it is shown that the decision of the homogeneous wave equation in the form of “belated” potentials is simultaneously and the decision of the equations of movement of a liquid, and “outstripped” potentials does not satisfy them. The analysis of coefficients of reflection and passage of running waves in non-uniform space is carried out. It is shown that on boundary of spaces with different sound speeds, a turning point of a sound wave is the point of full internal reflection. The way of calculation of coefficients of reflection and passage is offered by consideration of all three waves on boundary of spaces as vectors with the set directions and amplitude of a falling wave. Calculation of coefficients of reflection and passage of a sound wave in a wave-guide of canonical type along the chosen trajectory by two methods—under traditional formulas and a vector method is carried out. Results of calculation practically coincide. 展开更多
关键词 Sound Running waves wave Equation Reflection PASSAGE LIQUID space wave-GUIDE RAYS
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Time domain method for calculating free field motion of a layered half-space subjected to obliquely incident body waves 被引量:1
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作者 李山有 朱海燕 高淑芳 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2007年第2期191-196,共6页
In numerical simulation of wave scattering under oblique incident body waves using the finite element method, the free field motion at the incident lateral boundary induced by the background layered half-space complic... In numerical simulation of wave scattering under oblique incident body waves using the finite element method, the free field motion at the incident lateral boundary induced by the background layered half-space complicates the computational area. In order to replace the complex frequency domain method, a time-domain method to calculate the free field motion of a layered half-space subjected to oblique incident body waves is developed in this paper. The new method decouples the equations of motion used in the finite element method and offers an interpolation formula of the free field motion. This formula is based on the fact that the apparent horizontal velocity of the free field motion is constant and can be calculated exactly. Both the theoretical analysis and numerical results demonstrate that the proposed method offers a high degree of accuracy. 展开更多
关键词 layered half-space wave scattering obliquely incidence artificial botmdary explicit finite element method Snell law
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Forming of Space Charge Wave with Broad Frequency Spectrum in Helical Relativistic Two-Stream Electron Beams 被引量:1
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作者 A.Lysenko I.Volk +1 位作者 A.Serozhko O.Rybalko 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第7期150-154,共5页
We elaborate a quadratic nonlinear theory of plural interactions of growing space charge wave (SCW) harmonics during the development of the two-stream instability in helical relativistic electron beams. It is found ... We elaborate a quadratic nonlinear theory of plural interactions of growing space charge wave (SCW) harmonics during the development of the two-stream instability in helical relativistic electron beams. It is found that in helical two-stream electron beams the growth rate of the two-stream instability increases with the beam entrance angle. An SCW with the broad frequency spectrum, in which higher harmonics have higher amplitudes, forms when the frequency of the first SCW harmonic is much less than the critical frequency of the two-stream instability. For helical electron beams the spectrum expands with the increase of the beam entrance angle. Moreover, we obtain that utilizing helical electron beams in multiharmonic two-stream superheterodyne free-electron lasers leads to the improvement of their amplification characteristics, the frequency spectrum broadening in multiharmonic signal generation mode, and the reduction of the overall system dimensions. 展开更多
关键词 SCW Forming of space Charge wave with Broad Frequency Spectrum in Helical Relativistic Two-Stream Electron Beams
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Dynamic soil-tunnel interaction in layered half-space for incident P-and SV-waves 被引量:4
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作者 Jia Fu Jianwen Liang Lin Qin 《Earthquake Science》 CSCD 2015年第4期275-284,共10页
The dynamic soil-tunnel interaction is studied by the model of a rigid tunnel embedded in layered half-space, which is simplified as a single soil layer on elastic bedrock to the excitation of P- and SV-waves. The ind... The dynamic soil-tunnel interaction is studied by the model of a rigid tunnel embedded in layered half-space, which is simplified as a single soil layer on elastic bedrock to the excitation of P- and SV-waves. The indirect boundary element method is used, combined with the Green' s function of distributed loads acting on inclined lines. It is shown that the dynamic characteristics of soil-tunnel interaction in layered half-space are different much from that in homoge- neous half-space, and that the mechanism of soil-tunnel interaction is also different much from that of soil-founda- tion-superstructure interaction. For oblique incidence, the tunnel response for in-plane incident SV-waves is com- pletely different from that for incident SH-waves, while the tunnel response for vertically incident SV-wave is very similar to that of vertically incident SH-wave. 展开更多
关键词 Underground tunnel Layered half-space P-wave and SV-wave Indirect boundary element method Soil-tunnel interaction ~ Site dynamic characteristics
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Dynamic soil-tunnel interaction in layered half-space for incident plane SH waves 被引量:7
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作者 Fu Jia Liang Jianwen Qin Lin 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2016年第4期715-727,共13页
The dynamic soil-tunnel interaction is studied by indirect boundary element method (IBEM), using the model of a rigid tunnel in layered half-space, which is simplified to a single soil layer on elastic bedrock, subj... The dynamic soil-tunnel interaction is studied by indirect boundary element method (IBEM), using the model of a rigid tunnel in layered half-space, which is simplified to a single soil layer on elastic bedrock, subjected to incident plane SH waves. The accuracy of the results is verified through comparison with the analytical solution. It is shown that soil-tunnel interaction in layered half-space is larger than that in homogeneous half-space and this interaction mechanism is essentially different from that of soil-foundation-superstructure interaction. 展开更多
关键词 underground tunnel layered half-space plane SH wave indirect boundary element method soil-tunnel interaction site dynamic characteristics
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2.5D scattering of incident plane SV waves by a canyon in layered half-space 被引量:9
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作者 Ba Zhenning Liang Jianwen 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2010年第4期587-595,共9页
This paper presents a 2.5D scattering of incident plane SV waves by a canyon in a layered half-space by using the indirect boundary element method (IBEM). A free field response analysis is performed to provide the d... This paper presents a 2.5D scattering of incident plane SV waves by a canyon in a layered half-space by using the indirect boundary element method (IBEM). A free field response analysis is performed to provide the displacements and stresses on the boundary of the canyon where fictitious uniform moving loads are applied to calculate the Green's fi.mctions for the displacements and stresses. The amplitudes of the loads are determined by the boundary conditions. The free field displacements are added to the fictitious uniform moving loads induced displacements and the total response is obtained. Numerical calculations are performed for a canyon with homogenous and in one layer over bedrock. The effects of the thickness and stiffness of the layer on the amplification are studied and discussed. 展开更多
关键词 layered half-space CANYON plane SV wave AMPLIFICATION SCATTERING surface layer indirect boundaryelement method
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Plural interactions of space charge wave harmonics during the development of two-stream instability
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作者 Victor Kulish Alexander Lysenko +2 位作者 Michael Rombovsky Vitaliy Koval Iurii Volk 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第9期332-336,共5页
We construct a cubically nonlinear theory of plural interactions between harmonics of the growing space charge wave(SCW) during the development of the two-stream instability. It is shown that the SCW with a wide fre... We construct a cubically nonlinear theory of plural interactions between harmonics of the growing space charge wave(SCW) during the development of the two-stream instability. It is shown that the SCW with a wide frequency spectrum is formed when the frequency of the first SCW harmonic is much lower than the critical frequency of the two-stream instability.Such SCW has part of the spectrum in which higher harmonics have higher amplitudes. We analyze the dynamics of the plural harmonic interactions of the growing SCW and define the saturation harmonic levels. We find the mechanisms of forming the multiharmonic SCW for the waves with frequencies lower than the critical frequency and for the waves with frequencies that exceed the critical frequency. 展开更多
关键词 two-stream instability three-wave parametric resonances space charge wave free-electron laser
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Surface effect on Bleustein-Gulyaev wave in a piezoelectric half-space 被引量:2
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作者 Weiqiu Chen a) Department of Engineering Mechanics,Zhejiang University,Yuquan Campus,Hangzhou 310027,China 《Theoretical & Applied Mechanics Letters》 CAS 2011年第4期11-14,共4页
Surface effect,which is attributed to the different environment surrounding the surface or near-surface atoms from that embracing the bulk atoms,may become significant when the surface-to-volume ratio of a body is lar... Surface effect,which is attributed to the different environment surrounding the surface or near-surface atoms from that embracing the bulk atoms,may become significant when the surface-to-volume ratio of a body is large.This paper considers the effect of a plane boundary of a piezoelectric body modeled as a thin layer with specified material properties,for which a transfer relation between the state vectors at the top and bottom surfaces is derived based on the state-space formulations.The equations of surface piezoelectricity for different orders without any bias field are then presented by making use of the power series expression of the transfer matrix.The surface effect is demonstrated by considering the Bleustein-Gulyaev wave existing in a horizontally polarized piezoceramic half-space. 展开更多
关键词 surface piezoelectricity plane boundary state-space formalism Bleustein-Gulyaev wave
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Diffraction of plane P waves by a canyon of arbitrary shape in poroelastic half-space (Ⅱ): Numerical results and discussion 被引量:6
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作者 Jianwen Liang Zhongxian Liu 《Earthquake Science》 CSCD 2009年第3期223-230,共8页
This paper investigates in detail the nature of diffraction of plane P waves around a canyon in poroelastic half-space, and studies the effects of incident frequency, drainage condition, porosity, etc, on the diffract... This paper investigates in detail the nature of diffraction of plane P waves around a canyon in poroelastic half-space, and studies the effects of incident frequency, drainage condition, porosity, etc, on the diffraction of waves. It is shown that the surface displacement amplitudes of the drained case are close to those of the undrained case, however, the surface displacement amplitudes of the dry case are very different from those of the saturated (either drained or undrained) cases. There are large phase shift between the dry case and the saturated cases, as well as slightly longer resultant wavelengths for the undrained case than those for the drained case and longer resultant wavelengths for the drained case than those for the dry case. For small porosity the surface displacement amplitudes for the saturated cases are almost identical to those for the dry case; while for large porosity, the effect of drainage condition becomes significant, and the surface displacement amplitudes for the undrained case are larger than those for the drained case. As the incident frequency increases, the effect of porosity becomes significant, and more significant for the undrained case than that for the drained case. As the porosity increases, the pore pressures increase significantly but their oscillations become smoother. As the incident frequency increases, the pore pressures become more complicated. 展开更多
关键词 poroelastic half-space CANYON DIFFRACTION plane P wave surface displacement pore pressure
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An IBEM solution to the scattering of plane SH-waves by a lined tunnel in elastic wedge space 被引量:8
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作者 Zhongxian Liu Lei Liu 《Earthquake Science》 CSCD 2015年第1期71-86,共16页
The indirect boundary element method (IBEM) is developed to solve the scattering of plane SH-waves by a lined tunnel in elastic wedge space. According to the theory of single-layer potential, the scattered-wave fiel... The indirect boundary element method (IBEM) is developed to solve the scattering of plane SH-waves by a lined tunnel in elastic wedge space. According to the theory of single-layer potential, the scattered-wave field can be constructed by applying virtual uniform loads on the surface of lined tunnel and the nearby wedge surface. The densities of virtual loads can be solved by establishing equations through the continuity conditions on the interface and zero-traction conditions on free surfaces. The total wave field is obtained by the superposition of free field and scattered-wave field in elastic wedge space. Numerical results indicate that the IBEM can solve the diffraction of elastic wave in elastic wedge space accurately and effi- ciently. The wave motion feature strongly depends on the wedge angle, the angle of incidence, incident frequency, the location of lined tunnel, and material parameters. The waves interference and amplification effect around the tunnel in wedge space is more significant, causing the dynamic stress concentration factor on rigid tunnel and the displacement amplitude of flexible tunnel up to 50.0 and 17.0, respectively, more than double that of the case of half-space. Hence, considerable attention should be paid to seismic resistant or anti-explosion design of the tunnel built on a slope or hillside. 展开更多
关键词 Wedge space SCATTERING Lined tunnelPlane SH-waves Indirect boundary element method(IBEM) Dynamic stress concentration
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Diffraction of plane P waves by a canyon of arbitrary shape in poroelastic half-space (Ⅰ): Formulation 被引量:10
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作者 Jianwen Liang Zhongxian Liu 《Earthquake Science》 CSCD 2009年第3期215-222,共8页
This paper presents an indirect boundary integration equation method for diffraction of plane P waves by a two-dimensional canyon of arbitrary shape in poroelastic half-space. The Green's functions of compressional a... This paper presents an indirect boundary integration equation method for diffraction of plane P waves by a two-dimensional canyon of arbitrary shape in poroelastic half-space. The Green's functions of compressional and shear wave sources in poroelastic half-space are derived based on Biot's theory. The scattered waves are constructed using the fictitious wave sources close to the boundary of the canyon, and magnitude of the fictitious wave sources are determined by the boundary conditions. The precision of the method is verified by the satisfaction extent of boundary conditions, the comparison between the degenerated solutions of single-phased half-space and the well-known solutions, and the numerical stability of the method. 展开更多
关键词 poroelastic half-space CANYON DIFFRACTION plane P wave compressional wave source shear wave source Green's function
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A New Concept of Calculation Coefficietns of Reflection and Passage Sound Waves on the Boundary of Liquid Spaces
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作者 V. P. Ivanov G. K. Ivanova 《Open Journal of Acoustics》 2013年第3期72-79,共8页
It is consider that, from the standpoint of the law of conservation of energy, the process of converting sound wave falls on the boundary between two spaces in two, leaving the boundary, reflected and passage. It is a... It is consider that, from the standpoint of the law of conservation of energy, the process of converting sound wave falls on the boundary between two spaces in two, leaving the boundary, reflected and passage. It is assumed that the simultaneous presence of three waves is impossible, and that the process of converting one wave in two waves occurs instantaneously. Based on this concept, enter the following boundary conditions for the calculation of amplitudes (coefficients) of the reflected and passage waves. The initial phases of the reflected and passage waves coincide with the phase of the falling wave. The energy of the falling wave is equal to the sum of the energies of the reflected and passage waves. The normal component velocity amplitude of the particle of the liquid under the influence of the falling wave is equal to the sum of the normal component of particle velocity amplitudes of the reflected and passage waves. It was found that the character of dependence of the reflection coefficient on the angle of departure of the initial wave is the same as in the traditional formulas, but the coefficient of passage does not exceed unity. Calculations of reflection and passage coefficients for different values of the refractive coefficient at the boundary between two homogeneous spaces as well as the canonical form of the waveguide, wherein the speed of sound which is minimum at predetermined depth is carried out. 展开更多
关键词 Sound Running waves TRAJECTORY Phase REFLECTION PASSAGE LIQUID space wave-GUIDE
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Power and Cross-Spectra for the Turbulent Atmospheric Motion and Transports in the Domain of Wave Number Frequency Space: Theoretical Aspects
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作者 M. Y. Totagi 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1994年第4期491-498,共8页
The study of large-scale atmospheric turbulence and transport processes is of vital importance in the general circulation of the atmosphere. The governing equations of the power and cross-spectra for the atmospheric m... The study of large-scale atmospheric turbulence and transport processes is of vital importance in the general circulation of the atmosphere. The governing equations of the power and cross-spectra for the atmospheric motion and transports in the domain of wave number frequency space have been derived. The contributions of the nonlinear interactions of the atmospheric waves in velocity and temperature fields to the conversion of kinetic and potential energies and to the meridional transports of angular momentum and sensible heat in the atmosphere have been discussed. 展开更多
关键词 Spectral analysis Fourier transform Power and cross-spectra Atmospheric turbulence wave number frequency space Kinetic and potential energies Transports of angular momentum and sensible heat
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Diffraction of plane SV waves by a cavity in poroelastic half-space 被引量:15
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作者 Liang Jianwen and Liu Zhongxian Department of Civil Engineering, Tianjin University, Tianjin 300072, China Professor PhD Candidate 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2009年第1期29-46,共18页
This paper presents an indirect boundary integration equation method for diffraction of plane SV waves by a 2-D cavity in a poroelastic half-space.The Green's functions of compressive and shear wave sources are deriv... This paper presents an indirect boundary integration equation method for diffraction of plane SV waves by a 2-D cavity in a poroelastic half-space.The Green's functions of compressive and shear wave sources are derived based on Biot's theory. The scattered waves are constructed using fictitious wave sources close to the boundary of the cavity, and their magnitudes are determined by the boundary conditions. Verification of the accuracy is performed by: (1) checking the satisfaction extent of the boundary conditions, (2) comparing the degenerated solutions of a single-phased case with well- known solutions, and (3) examining the numerical stability of the solutions. The nature of diffraction of plane SV waves around a cavity in a poroelastic half-space is investigated by numerical examples. 展开更多
关键词 poroelastic half-space CAVITY DIFFRACTION plane SV waves compressive wave source shear wave source Green's function pore pressure
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Influence of two-stream relativistic electron beam parameters on the space-charge wave with broad frequency spectrum formation
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作者 Alexander LYSENKO Iurii VOLK 《Plasma Science and Technology》 SCIE EI CAS CSCD 2018年第3期10-18,共9页
We developed a cubic non-linear theory describing the dynamics of the multiharmonic spacecharge wave(SCW), with harmonics frequencies smaller than the two-stream instability critical frequency, with different relati... We developed a cubic non-linear theory describing the dynamics of the multiharmonic spacecharge wave(SCW), with harmonics frequencies smaller than the two-stream instability critical frequency, with different relativistic electron beam(REB) parameters. The self-consistent differential equation system for multiharmonic SCW harmonic amplitudes was elaborated in a cubic non-linear approximation. This system considers plural three-wave parametric resonant interactions between wave harmonics and the two-stream instability effect. Different REB parameters such as the input angle with respect to focusing magnetic field, the average relativistic factor value, difference of partial relativistic factors, and plasma frequency of partial beams were investigated regarding their influence on the frequency spectrum width and multiharmonic SCW saturation levels. We suggested ways in which the multiharmonic SCW frequency spectrum widths could be increased in order to use them in multiharmonic two-stream superheterodyne free-electron lasers, with the main purpose of forming a powerful multiharmonic electromagnetic wave. 展开更多
关键词 space-charge wave relativistic electron beam two-stream instability PARAMETRIC
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Numerical Simulations of Nonlinear Interaction of Space Charge Waves in Microwave and Millimeter Wave Range in n-InN Films Using Negative Differential Conductivity
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作者 Abel Garcia-Barrientos Volodymyr Grimalsky 《Modeling and Numerical Simulation of Material Science》 2014年第3期136-142,共7页
Numerical simulations of nonlinear interaction of space charge waves in microwave and millimeter wave range in n-InN films have been carried out. A micro- and millimeter-waves frequency conversion using the negative d... Numerical simulations of nonlinear interaction of space charge waves in microwave and millimeter wave range in n-InN films have been carried out. A micro- and millimeter-waves frequency conversion using the negative differential conductivity phenomenon is carried out when the harmonics of the input signal are generated. An increment in the amplification is observed in n-InN films at essentially at high-frequencies f < 450 GHz, when compared with n-GaAs films f < 44 GHz. This work provides a way to achieve a frequency conversion and amplification of micro- and millimeter-waves. 展开更多
关键词 space CHARGE waveS INN Film NEGATIVE DIFFERENTIAL CONDUCTIVITY
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A whole-space transform formula of cylindrical wave functions for scattering problems 被引量:1
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作者 Yuan Xiaoming 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2014年第1期23-28,共6页
The theory of elastic wave scattering is a fundamental concept in the study of elastic dynamics and wave motion,and the wave function expansion technique has been widely used in many subjects.To supply the essential t... The theory of elastic wave scattering is a fundamental concept in the study of elastic dynamics and wave motion,and the wave function expansion technique has been widely used in many subjects.To supply the essential tools for solving wave scattering problems induced by an eccentric source or multi-sources as well as multi-scatters,a whole-space transform formula of cylindrical wave functions is presented and its applicability to some simple cases is demonstrated in this study.The transforms of wave functions in cylindrical coordinates can be classifi ed into two basic types: interior transform and exterior transform,and the existing Graf’s addition theorem is only suitable for the former.By performing a new replacement between the two coordinates,the exterior transform formula is fi rst deduced.It is then combined with Graf’s addition theorem to establish a whole-space transform formula.By using the whole-space transform formula,the scattering solutions by the sources outside and inside a cylindrical cavity are constructed as examples of its application.The effectiveness and advantages of the whole-space transform formula is illustrated by comparison with the approximate model based on a large cycle method.The whole-space transform formula presented herein can be used to perform the transform between two different cylindrical coordinates in the whole space.In addition,its concept and principle are universal and can be further extended to establish the coordinate transform formula of wave functions in other coordinate systems. 展开更多
关键词 scattering transform of wave functions whole-space transform eccentric source multi-sources multi-scatters
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Influence of Nonlocality on Amplification of Space Charge Waves in n-GaN Films
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作者 Volodymyr Grimalsky Svetlana Koshevaya +1 位作者 Margarita Tecpoyotl-T. Fernanda Diaz-A. 《Journal of Electromagnetic Analysis and Applications》 2011年第2期33-38,共6页
It is investigated theoretically the amplification of space charge waves (SCWs) due to the negative differential conduc-tivity (NDC) in n-GaN films of submicron thicknesses placed onto a semi-infinite substrate. The i... It is investigated theoretically the amplification of space charge waves (SCWs) due to the negative differential conduc-tivity (NDC) in n-GaN films of submicron thicknesses placed onto a semi-infinite substrate. The influence of the nonlo-cal dependence of the average electron velocity on the electron energy is considered. The simplest nonlocal model is used where the total electron concentration is taken into account. The relaxation momentum and energy frequencies have been calculated. The influence of the nonlocality on NDC results in the decrease of the absolute value of its real part and appearance of the imaginary part. The calculation of the diffusion coefficient leads to essential errors. The simulations of spatial increments of the amplification of SCWs demonstrate that the nonlocality is essential at the fre-quencies f ? 150 GHz, and the amplification is possible up till the frequencies f ? 400 ??? 500 GHz. 展开更多
关键词 GALLIUM NITRIDE Films Negative Differential CONDUCTIVITY space Charge waveS AMPLIFICATION NONLOCALITY
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