首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
A molecular dynamical simulation method is used to investigate the diffusion of the two-dimensional magnetized dusty plasmas. The effects of charge and mass of the particles, as well as the external magnetic field are discussed in detail. It is shown that, relative to the mass of particulate, the charge and magnetic field have a more considerable effect on the diffusion process, particularly on the resulting structure of the system. The dependence of diffusion coefficient on the temperature is shown to be linearly changed over a wide range of temperature.  相似文献   

2.
The energy spectrum of mobile charge carriers in a two-dimensional Antiferromagnet placed in external magnetic field is analyzed. It is shown that allowing for the magnetic sublattice skew the effective mass of mobile charge carriers in a lightly doped Antiferromagnet. This affects substantially the transport and thermodynamic properties of the system. A insulator-semimetal transition is induced with external magnetic field.  相似文献   

3.
A theoretical investigation of the full-circle arc located between two planes is presented. The circular arc shape is due to an applied magnetic field. The basic equations for conservations of mass, momentum, energy, and charge, as well as Maxwell's equations and the equation of state lead to a coupled set of partial differential equations. By means of Green's formula, this set is transformed into a set of integral equations. Using the analytically known Green's function, the system may be solved by an iteration procedure. For a simplified arc model, the quantities of interest are computed: The temperature distribution, the mass flow field, and the external magnetic field necessary to maintain this arc configuration.  相似文献   

4.
Gravitomagnetic charge that can also be referred to as the dual mass or magnetic mass is the topological charge in gravity theory. A gravitomagnetic monopole at rest can produce a stationary gravitomagnetic field. Due to the topological nature of gravitomagnetic charge, the metric of spacetime where the gravitomagnetic matter is present will be nonanalytic. In this paper both the dual curvature tensors (which can characterize the dynamics of gravitational charge/monopoles) and the antisymmetric gravitational field equation of gravitomagnetic matter are presented. We consider and discuss the mathematical formulation and physical properties of the dual curvature tensors and scalar, antisymmetric source tensors, dual spin connection (including the low‐motion weak‐field approximation), dual vierbein field as well as dual current densities of gravitomagnetic charge. It is shown that the dynamics of gravitomagnetic charge can be founded within the framework of the above dual quantities. In addition, the duality relationship in the dynamical theories between the gravitomagnetic charge (dual mass) and the gravitoelectric charge (mass) is also taken into account in the present paper.  相似文献   

5.
Characteristics of nonlinear gauge-invariant singularity-free field theories of elementary particles are discussed. It is shown that the electromagnetic field, in conjunction with a scalar field which is required for gauge invariance, provides a potential mechanism for the creation of the spin and magnetic moment of the particle, in addition to its mass and charge.  相似文献   

6.
本文讨论了不可易SU(2)规范场的各种规范不变物理量——电荷、对偶荷(磁荷)、电磁场以及有质量矢粒子场的表达式与关系,特别是对偶荷(磁荷)与电荷算符同位旋方向的大范围拓扑性质的关系。  相似文献   

7.
Within the framework of the kinetic energy driven superconductivity, the electromagnetic response in cuprate superconductors is studied in the linear response approach. The kernel of the response function is evaluated and employed to calculate the local magnetic field profile, the magnetic field penetration depth, and the superfluid density, based on the specular reflection model for a purely transverse vector potential. It is shown that the low temperature magnetic field profile follows an exponential decay at the surface, while the magnetic field penetration depth depends linearly on temperature, except for the strong deviation from the linear characteristics at extremely low temperatures. The superfluid density is found to decrease linearly with decreasing doping concentration in the underdoped regime. The problem of gauge invariance is addressed and an approximation for the dressed current vertex, which does not violate local charge conservation is proposed and discussed.  相似文献   

8.
The symplectic tomograms of coherent states of a charged particle moving in a constant uniform magnetic field are obtained in explicit form. The tomograms are shown to coincide with normal probability distributions of two random variables. The means and dispersions of the variables are found and expressed in terms of means and dispersions of the charged particle coordinates and momenta. The characteristic function of the tomographic probability distribution is found. The center of mass tomogram of the coherent state of charge in magnetic field is also found and the relation of the symplectic tomogram and the center of mass tomogram is established.  相似文献   

9.
The vertex function for a virtual massive neutrino is calculated in the limit of soft real photons. A method based on employing the neutrino self-energy operator in a weak external electromagnetic field in the approximation linear in the field is developed in order to render this calculation of the vertex function convenient. It is shown that the electric charge and the electric dipole moment of the real neutrino are zero; only the magnetic moment is nonzero for massive neutrinos. A fourth-generation heavy neutrino of mass not less than half of the Z-boson mass is considered as a massive neutrino.  相似文献   

10.
We study here the onset of charge density wave instabilities in quantum Hall systems at finite temperature for Landau level filling nu>4. Specific emphasis is placed on the role of disorder as well as on an in-plane magnetic field. Beyond some critical value, disorder is observed to suppress the charge density wave melting temperature to zero. In addition, we find that a transition from perpendicular to parallel stripes (relative to the in-plane magnetic field) exists when the electron gas thickness exceeds approximately 60 A. The perpendicular alignment of the stripes is in agreement with the experimental finding that the easy conduction direction is perpendicular to the in-plane field.  相似文献   

11.
在伦敦方程和电磁场的洛伦兹变换的基础上讨论了在磁场中运动的第一类超导平板的电磁性质。结果表明临界磁场将随超导体的速度的增加而减小 ;在穿透层内有一指数衰减的屏蔽电荷分布 ,其符号与超导体表面由运动感生的电荷相反、数量相等。屏蔽电荷屏蔽了表面电荷产生的感应电场 ,使电场和磁场一样在穿透层内指数衰减 ,在远离表面的内部 ,感应电场被完全屏蔽  相似文献   

12.
不可压缩等离子体的2维磁场重联模型   总被引:1,自引:1,他引:0       下载免费PDF全文
提出了一种2维磁场重联模型。磁场重联过程中的电荷分离在等离子体中产生静电场,等离子体在电场中的漂移运动可以解释阿尔芬速度量级的出流。该磁场重联模型给出如下结论:Sweet-Parker模型描述的重联率强烈地依赖于电子质量与离子质量之比;反常电阻率正比于离子惯性长度和电流片宽度比值的平方; 相对论效应和高温等离子体中电子-正电子对的产生可以提高重联率; 电磁波的激发对于磁能的损耗是必要的。  相似文献   

13.
Experiments on creating an axial magnetic field in the metallic sheath of a shaped charge immediately before explosion are reported. Under such conditions, the penetrability of the charge is shown to decrease substantially. For instance, the penetration into a steel target is reduced more than twice when the initial field in the sheath is several tenths of a tesla. The most plausible reason for this effect is a drastic rise in the magnetic field (to a level as high as several hundreds of teslas) in the jet formation area, which disturbs the cumulative jet formation process. This pumping effect is presumably related to the magnetic field “freezing” into the deforming conductive material. Such a mechanism shows up when the tensile strain of the sheath’s fragments along the magnetic flux lines is significant. The ability of the deformation mechanism of field generation to disturb greatly the jet formation process upon collapsing the shaped charge sheath is substantiated by calculations.  相似文献   

14.
The magnetic screening in cold electroweak matter at high density of leptons JLMW3/6π2 is investigated within the approximation known to guarantee the Bose-Einstein condensation of W±-mesons. It is shown that the photon in this medium acquires a magnetic mass, the electro-magnetic field becoming short-range. It is found that the Meissner damping of a magnetic field is provided in this approximation first of all by an induced polarization charge of weak nature.  相似文献   

15.
We have obtained expressions of the accelerating effect in Kerr-Newman Kasuya field. These expressionsinclude four parameters: mass m, angular momentum a, electric charge q, and magnetic charge φ. Furthermore we studyits special case (vi = 0). We get the following conclusion. In the gravitation field of souse mass with electric charge qand magnetic charge b, the acceleration of test particle has not only radial component but also transverse component.When θ = 0, the acceleration is minimum, and when θ = π/2, the acceleration is maximum. Furthermore, we discussthe effects of electric charge q and magnetic charge φ respectively.  相似文献   

16.
龚添喜  王永久 《物理学报》2009,58(9):5988-5992
计算了带有电荷和磁荷的旋转场源外部稳态时空中光子的轨道效应. 通过对计算结果的分析, 发现由荷电所引起的光子轨道偏转效应将减小由场源质量所引起的光子轨道偏转效应,但由场源的旋转所引起的相应偏转效应将依赖于场源的旋转方向与光子运动方向之间的夹角. 通过对相应的天体参数的讨论得到了一系列有意义的结果. 关键词: 光子轨道 引力效应 稳态时空  相似文献   

17.
Recently we demonstrated theoretically that the carriers of quantized angular momentum in superconductors are not the Cooper pairs but the lattice ions, which must execute coherent localized motion consistent with the phenomenon of superconductivity. We demonstrate here that in the presence of an external magnetic field, the free superelectron and bound ion currents largely cancel providing a self-consistent microscopic and macroscopic interpretation of near-zero magnetic permeability inside superconductors. The neutral mass currents, however, do not cancel, because of the monopolar gravitational charge. It is shown that the coherent alignment of lattice ion spins will generate a detectable gravitomagnetic field, and in the presence of a time-dependent applied magnetic vector potential field, a detectable gravitoelectric field.  相似文献   

18.
In Abelian monopole theories the magnetic coupling is required to be enormous. Using the electric-magnetic duality of electromagnetism, it is argued that the existence of such a large, nonperturbative magnetic coupling should lead to a phase transition where magnetic charge is permanently confined and the photon becomes massive. The apparent masslessness of the photon could then be used as an argument against the existence of such a large, nonperturbative magnetic charge. Finally it is shown that even in the presence of this conjectured dynamical mass generation the Cabbibo-Ferrari (1962) formulation of magnetic charge gives a consistent theory.  相似文献   

19.
Results for the influence of electron-phonon interaction on the cyclotron effective mass and the resonance linewidth in a two-dimensional electron gas are presented. The temperature and magnetic field dependence is studied and the existence of quantum oscillations is demonstrated. It is shown that the relevant phonon frequency in typical MOS inversion layers is very small so that magneto-transport properties are temperature dependent even at a few degrees Kelvin. Results are consistent with the observed temperature, magnetic field and frequency dependence in Si(100) inversion layers.  相似文献   

20.
It is shown that the electrodynamics of orthogonal magnetic and electric fields can be represented as the dynamics of covariant lines of force. Such a representation is provided for the Lienard-Wichert field of an arbitrary moving charge and the field of a charge that moves uniformly about a circle. The four vector of the electric lines of force is written as the sum of the four vector of the charge and the radius four vector directed along the light cone to the observation point. This vector is a solution of an equation that formally coincides with the equation of motion of the magnetic moment in external fields for a zero intrinsic magnetic moment. The electromagnetic field is reconstructed according to a system of lines that correspond to the total equation of motion of the magnetic moment. Such a field for a uniformly circulating charge is examined.Erevan Physics Institute. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 35, Nos. 3, 4, pp. 313–323, March–April, 1992.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号