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1.
We construct the two-component supersymmetric generalized Harry Dym equation which is integrable and study various properties of this model in the bosonic limit. We obtain in this limit a new integrable system which, under a hodograph transformation, reduces to a coupled three-component system. We show how the Hamiltonian structure transforms under a hodograph transformation and study the properties of the model under a further reduction to a two-component system.  相似文献   

2.
We study the effective parameters of a three-component plane dielectric medium with a doubly periodic arrangement of circular inclusions. The problem is solved in the one-dipole approximation. The computational results are compared with a two-component Rayleigh model. The general structure of the formulas for the effective parameters is discussed and the reciprocity relations for a three-component matrix system are determined. Explicit expressions are given for the dielectric permittivity when the concentration of circular inclusions is low, and their domain of applicability is determined. Under certain polarization conditions, the effective conductivity in a three-component medium is exactly equal to the dielectric permittivity of the matrix. Zh. éksp. Teor. Fiz. 114, 1121–1136 (September 1998)  相似文献   

3.
The development of new fiber Bragg grating (FBG)-based multi-component force sensors is described. A two-component and a three-component force sensor have been fabricated and tested. The two-component force sensor measures the normal and the longitudinal shear component of the force. The three-component force sensor measures the normal, the longitudinal shear and the transverse shear component, and thus provides the magnitude as well as the direction of the force in the three-dimensional space. In the two-component sensor, one FBG is embedded rectilinearly and another non-rectilinearly within carbon composite layer. In the three-component force sensor, one FBG is embedded rectilinearly and two mutually perpendicular FBGs non-rectilinearly within the carbon composite layer. This paper presents the basic sensor structure and the proof-of-concept experimental demonstration of the two sensors. Force measurement within the range 0–15 N has been successfully conducted within 10% deviation.  相似文献   

4.
研究了两组分玻色-爱因斯坦凝聚体(BECs)在一维光晶格中的隧穿动力学及周期调制效应.在两模近似下,运用数值分析的方法,讨论了两组分间相互作用对体系的隧穿动力学行为的影响.进一步讨论了两组分间相互作用在周期调制下系统的动力学特性,分析了随着调制振幅和频率的变化,系统发生隧穿、不稳定和自俘获的区域分布,发现在中低频调制下,系统的隧穿动力学发生了明显的改变.  相似文献   

5.
One of the fundamental questions for self-organization in pattern formation is how spatial periodic structure is spontaneously formed starting from a localized fluctuation. It is known in dissipative systems that splitting dynamics is one of the driving forces to create many particle-like patterns from a single seed. On the way to final state there occur many collisions among them and its scattering manner is crucial to predict whether periodic structure is realized or not. We focus on the colliding dynamics of traveling spots arising in a three-component system and study how the transition of scattering dynamics is brought about. It has been clarified that hidden unstable patterns called "scattors" and their stable and unstable manifolds direct the traffic flow of orbits before and after collisions. The collision process in general can be decomposed into several steps and each step is controlled by such a scattor, in other words, a network among scattors forms the backbone for scattering dynamics. A variety of input-output relations comes from the complexity of the network as well as high Morse indices of the scattor. The change of transition manners is caused by the switching of the network from one structure to another, and such a change is caused by the singularities of scattors. We illustrate a typical example of the change of transition caused by the destabilization of the scattor. A new instability of the scattor brings a new destination for the orbit resulting in a new input-output relation, for instance, Hopf instability for the scattor of peanut type brings an annihilation.  相似文献   

6.
《Nuclear Physics A》1997,622(4):538-552
Quantum effects inside the chiral bag induce a color anomaly which requires a compensating surface term to prevent breakdown of color gauge invariance. We show that the presence of this surface term first discovered several years ago allows one to derive in a gauge-invariant way a chiral-bag version of the Shore-Veneziano two-component formula for the flavor-singlet axial charge of the proton. This has relevance to what is referred to as the “proton spin problem” on the one hand and to the Cheshire-Cat phenomenon in hadron structure on the other. We show that when calculated to the leading order in the color gauge coupling and for a specific color electric monopole configuration in the bag, one can obtain a striking Cheshire-Cat phenomenon with a negligibly small singlet axial charge.  相似文献   

7.
In monopole-fermion dynamics, the boundary condition which is responsible for baryon number non-conservation also violates electric and color hypercharge conservation. We show by detailed calculations that actually the latter conservation laws are dynamically restored. It is shown that for a finite size monopole, there is a small but finite amplitude for the monopole ground state to make a virtual transition into a state containing a dyon and some fermions carrying equal and opposite charge as that of the dyon. But the amplitude for this state to make a virtual transition to a state carrying a net total charge is identically zero. The monopole ground state, as a result, is an eigenstate of electric charge even in the presence of massless fermions. We also calculate the four-body charge and chirality conserving but baryon number violating condensates, which exist independently of the existence of the anomaly and hence persist even in the presence of more generations of massless fermions.  相似文献   

8.
A correctable three-component inertial navigation system is suggested to be transformed into a two-component system capable of estimating the earth’s gravitational field. The results of a computational experiment are presented.  相似文献   

9.
李吉  刘伍明 《物理学报》2018,67(11):110302-110302
利用准二维Gross-Pitaevskii方程,研究了在梯度磁场中具有自旋-轨道耦合的旋转两分量玻色-爱因斯坦凝聚体的基态结构.探索了自旋-轨道耦合作用和梯度磁场对基态的影响.结果发现,在梯度磁场下,随着自旋-轨道耦合强度增大,基态结构由skyrmion格子逐渐过渡为skyrmion列.对于弱自旋-轨道耦合和小旋转频率情况,增大磁场梯度强度可导致基态由平面波相转变为half-skyrmion;对于强自旋-轨道耦合和大旋转频率情况,梯度磁场可诱导hidden涡旋的产生.梯度磁场、自旋-轨道耦合和旋转作为体系的调控参数,可用于控制不同基态相间的转化.  相似文献   

10.
钟宏华  谢琼涛  徐军  海文华  李朝红 《中国物理 B》2014,23(2):20314-020314
We investigate the nonlinear dissipative coherence bifurcation and population dynamics of a two-component atomic Bose-Einstein condensate coupling with a continuum. The coupling between the two-component condensates and the continuum brings effective dissipations to the two-component condensates. The steady states and the coherence bifurcation depend on both dissipation and the nonlinear interaction between condensed atoms. The coherence among condensed atoms may be even enhanced by the effective dissipations. The combination of dissipation and nonlinearity allows one to control the switching between different self-trapped states or the switching between a self-trapped state and a non-self-trapped state.  相似文献   

11.
We present a deformed ?-product for a particle in the presence of a magnetic monopole. The product is obtained within a self-dual quantization-dequantization scheme, with the correspondence between classical observables and operators defined with the help of a quaternionic Hilbert space, following work by Emch and Jadczyk. The resulting product is well defined for a large class of complex functions and reproduces (at first order in ?) the Poisson structure of the particle in the monopole field. The product is associative only for quantized monopole charges, thus incorporating Dirac's quantization requirement.  相似文献   

12.
The reflection and transmission coefficients of two-component and three-component dielectric multilayered periodic structures (2CODMS and 3CODMS) are derived using the transfer matrix method. The width of the high reflectance zone in the case of two-and three-component systems is derived and computed using suitable parameters. Numerical calculations for long-and short-wavelength cutoff band-pass filters of various structures are shown in a three-component system. Comparison is also done for 2CODMS for long-and short-wavelength cutoff filters. Spectral properties of interference reflection filters of the type [G(XY)A], whose components represent long-wavelength cutoff [X] and short-wavelength cutoff [Y], are also studied. The reflection and transmission bandwidth of the high reflectance zone is presented. Optimization is done in three-component systems to make it suitable for ideal long-and short-wavelength band-pass filters.  相似文献   

13.
We study the multi-peakon solutions for two new coupled Camassa-Holm equations, which include two-component and three-component Camassa-Holm equations. These multi-peakon solutions are shown in weak sense. In particular, the double peakon solutions of both equations are investigated in detail. At the same time, the dynamic behaviors of three types double peakon solutions are analyzed by some figures.  相似文献   

14.
Holographic recording techniques have recently been studied as a means to extend two-component, planar particle image velocimetry (PIV) techniques for three-component, whole-field velocity measurements. In a similar manner to two-component PIV, three-component, holographic PIV (HPIV) uses correlation-based techniques to extract particle displacement fields from double-exposure holograms. Since a holographic image contains information concerning both the phase and the amplitude of the scattered field it is possible to correlate either the intensity or the complex amplitude. In previous work we have shown that optical methods to compute the autocorrelation of the complex amplitude are inherently more tolerant to aberrations introduced in the reconstruction process, Coupland, Halliwell, Proc. Roy. Soc. 453 (1960) (1997) 1066. In this paper we introduce a new method of holographic recording and reconstruction that allows a constant image shift to be introduced to the particle image displacement. The technique, which we call conjugate reconstruction, resolves directional ambiguity and extends the dynamic range of HPIV. The theory of this method is examined in detail and a relationship between the image and object displacement is derived. Experimental verification of the theory is presented.  相似文献   

15.
We consider a single particle hopping on a tight binding lattice formed by the vertices of a regular polyhedron and discuss the effect of a magnetic monopole enclosed in the polyhedron. The presence of the monopole induces phases on the hopping terms, given by Peierls substitution. By requiring the flux through each face of a regular polyhedron to be the same, Dirac’s quantization condition is obtained in this discrete setting. For each regular polyhedron, we calculate the energy spectrum for an arbitrary value of the flux through a Dirac string coming in from one of the faces. We find that the energy levels are degenerate only when the flux through the Dirac string corresponds to a quantized monopole. We show that the degeneracies in the presence of the monopole can be classified using the double group of the symmetry of the polyhedron and label all energy levels with corresponding irreducible representations.  相似文献   

16.
王凯  朱京平  刘宏  侯洵 《中国物理 B》2016,25(9):94201-094201
Based on the three-component assumption that the reflection is divided into specular reflection,directional diffuse reflection,and ideal diffuse reflection,a bidirectional reflectance distribution function(BRDF) model of metallic materials is presented.Compared with the two-component assumption that the reflection is composed of specular reflection and diffuse reflection,the three-component assumption divides the diffuse reflection into directional diffuse and ideal diffuse reflection.This model effectively resolves the problem that constant diffuse reflection leads to considerable error for metallic materials.Simulation and measurement results validate that this three-component BRDF model can improve the modeling accuracy significantly and describe the reflection properties in the hemisphere space precisely for the metallic materials.  相似文献   

17.
Motivated by a recent proposal on the possibility of observing a monopole in the band structure, and by an increasing interest in the role of Berry phase in spintronics, we reconsidered the problem of adiabatic motion of a wave packet of Bloch functions, under a perturbation varying slowly and incommensurately to the lattice structure. We showed, using only the fundamental principles of quantum mechanics, that the effective wave-packet dynamics of Bloch electrons is conveniently described by a set of equations of motion (EOM) in which a non-Abelian Berry phase associated with the internal degree of freedom appears.  相似文献   

18.
Abstract

In the present work, we have numerically solved the dispersion equation of the surface wave propagating on a uniform collisional plasma column. The electric field and surface current distributions have been computed in different situations. We have investigated the effect of plasma frequency variation on the spatial distribution of the surface current. Results show that varying the electron density of the plasma column enables the plasma column to work as a plasma monopole antenna with a fixed geometrical structure and excited frequency which is able to create different radiation patterns. Our numerical analysis also shows that a little change in the radius of the plasma column has a strong influence on the current distribution at the excited frequency in RF region. This effect can be ignored in the usual (metallic) antenna while it is very important in designing of the plasma monopole antenna.  相似文献   

19.
20.
It has been shown that like-charged particles inside electroneutral plasma can be attracted to each other, in contrast with non-electroneutral plasma considered in the literature, where such particles electrostatically repulse when they have any distance between them. We have calculated an analytical formula for the free energy of electroneutral three-component two-temperature plasma, from the basis of the Poisson–Boltzmann electrostatic equation. It is shown that free energy has a local minimum when the temperature of electrons exceeds 2000 K, when the quantity of electrons is less than 20% of the total quantity of negatively charged particles, when the temperature of ions is 300 K and when the distance between ions is several Debye radii. Plasma of a specified structure, temperature and density can mimic a fireball substance, in contrast with, for example, two-component isothermal plasma which has no minimum free energy at any interparticle distance.  相似文献   

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