On the two-dimensional classical motion of a charged particle in an electromagnetic field with an additional quadratic integral of motion

The problem of quadratic Hamiltonians with an electromagnetic field commuting in the sense of the standard Poisson brackets has been considered. It has been shown that, as in the quantum case, any such pair can be reduced to the canonical form, which makes it possible to construct the complete classification of the solutions in the class of meromorphic solutions for the main function of one variable. The transformation to the canonical form is performed through the change of variables to the Kovalevskaya-type variables, which is similar to that in the theory of integrable tops. This transformation has been considered for the two-dimensional Hamiltonian of a charged particle with an additional quadratic integral of motion.     

Effects on planetary motion of an external electromagnetic field

By considering an uncharged mass embedded in an external electromagnetic field we show that the Einstein corrections to the Newtonian results may further be modified.     

On some integrable cases of the two-dimensional motion of a charged particle in an electromagnetic field

Two cases of the two-dimensional motion of a charged particle in an electromagnetic field have been integrated. In these cases, the Hamiltonian commutes with the angular momentum. Variables are separable in polar coordinates. The vector potential and potential energy have been taken from my recent work regarding two cases of the two-dimensional Schrödinger equation, which belong to quasi-exactly solvable problems. In these cases, semiclassical and exact wavefunctions have been compared in classically forbidden regions.     

On the motion of a particle in a magnetic trap with a secondary electromagnetic field

The adiabatic approximation of motion in the plane perpendicular to the magnetic induction B and the averaged motion in the direction parallel to B are derived from the Hamiltonian transformed to natural coordinates. Certain conservative properties of the field are shown. The conditions derived therefrom for magnetic traps with a cusped field are given.The author would like to thank J. Váa for support and J. atlov and J. Teichmann for criticism of this work.     

Entanglement control in a superconducting qubit system by an electromagnetic field

By making use of the dynamical algebraic method we investigate a quantum system consisting of superconducting qubits interacting with data buses, where the qubits are driven by time-dependent electromagnetic field and obtain an explicit expression of time evolution operator. Furthermore, we explore the entanglement dynamics and the influence of the time-dependent electromagnetic field and the initial state on the entanglement sudden death and birth for the system. It is shown that the entanglement between the qubit and bus as well as the entanglement sudden death and birth can be controlled by the time-dependent electromagnetic field.     

空间微弱电磁场的测试、屏蔽及应用

分析了空间电磁干扰对电镜等电子仪器的影响;讨论了电磁屏蔽的设计和空间磁场测试原理;采用自行设计的线包和微弱电磁场测试技术,分析实测了多家实验室,证明该方法简便易行;对检测输电线路的老化和微弱漏电也具有实际意义．     

Laser control of third-harmonic generation by means of an additional EM field

Control of the third-harmonic generation process through an external electromagnetic field is observed in atomic Ca. The conversion efficiency can be modified when the third harmonic is produced in the vicinity of an autoionizing state. A second laser is used to produce strong radiative coupling between a low-lying bound state and the autoionizing state.     

On the Hamiltonian nature of semiclassical equations of motion in the presence of an electromagnetic field and Berry curvature

We consider the semiclassical equations of motion of a particle when both an external electromagnetic field and the Berry gauge field in the momentum space are present. It is shown that these equations are Hamiltonian and relations between the canonical and covariant variables are determined through a consistent account of all components of the Berry connection. The Jacobian of the canonical-to-covariant-variables transformation describes the nonconservation of the ‘naive’ phase space volume in the covariant coordinates [D. Xiao, J. Shi, Q. Niu, Phys. Rev. Lett. 95 (2005) 137204].     

On the sensitivity of ion traps for spectroscopic applications

Ba⁺ ions, created by surface ionization near one endcap of an rf quadrupole trap were slowed down by collisions with the background gas. At He pressures of 10^?6 mbar or more 2% of the primary ions could be trapped. The sensitivity of ion detection by fluorescence radiation allows spectroscopic experiments, starting from less than 10⁷ particles. The observation of the ground-state hyperfine splitting of¹³⁷Ba⁺ is given as an example.     

On the separation of electronic and nuclear motion for molecules in an intense electromagnetic wave

The separation of electronic and nuclear variables is considered for a molecule in an intense electromagnetic field with frequency ω close to some electronic transition frequency. In this case the electron potential curves are essentially modified and a new branch of the vibrational spectrum can appear which has no counterpart in the original spectrum.     

Lorentz transformations for electromagnetic field vectors and the motion of charges in constant,homogeneous electromagnetic fields

A surface in velocity space which corresponds to Lorentz transformations minimizing the magnitudes of the vectors of a given electromagnetic field is formed. The relation with Lorentz transformations which do not change the magnitudes of the given electromagnetic field is indicated. The behavior of field vectors in a system of reference bound with a charge moving in a constant and homogeneous electromagnetic field is considered. It is shown that an electric charge in a constant and homogeneous electromagnetic field with inclusion of the effect of radiation reaction moves in such a manner that in the reference frame moving with it the magnitudes of the electromagnetic field vectors decrease and their directions approach one another. The time of transition to the state in which the field vectors in the system bound with the charge are mutually parallel is determined.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii Fizika, No. 11, pp. 63–67, November, 1971.     

Equation of motion of a particle in an external electromagnetic field in cylindrical coordinates

Translated from Isvetiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 34, No. 4, p. 435, April, 1991.     

纵磁结构真空灭弧室电磁场及电弧运动特性

为了了解纵向磁场下的电弧运动过程,建立了真空灭弧室的3维仿真模型。采用PIC模拟方法对12 kV灭弧室内的电磁场、电弧运动特性进行计算仿真。通过改变触头间距、屏蔽罩尺寸和触头开槽宽度,研究了灭弧室内的电场、磁场分布;对不同触头间距下随时间变化的电弧运动过程和触头表面的电弧分布情况进行了模拟计算。计算结果表明:在真空灭弧室中适当设置屏蔽罩,可有效改善灭弧室内的电场分布;触头铜基上的开槽宽度对磁场会产生影响,宽度越大,磁场强度越大。     

纵磁结构真空灭弧室电磁场及电弧运动特性

为了了解纵向磁场下的电弧运动过程,建立了真空灭弧室的3维仿真模型。采用PIC模拟方法对12 kV灭弧室内的电磁场、电弧运动特性进行计算仿真。通过改变触头间距、屏蔽罩尺寸和触头开槽宽度,研究了灭弧室内的电场、磁场分布;对不同触头间距下随时间变化的电弧运动过程和触头表面的电弧分布情况进行了模拟计算。计算结果表明：在真空灭弧室中适当设置屏蔽罩,可有效改善灭弧室内的电场分布;触头铜基上的开槽宽度对磁场会产生影响,宽度越大,磁场强度越大。     

On the electromagnetic field energy in an isotropic transparent nonlinear medium

Expressions for the energy density of an electromagnetic field in an isotropic transparent medium with cubic or higher order nonlinearity are derived. For comparatively long pulses, the local energy density is shown to depend not only on the squared modulus of the electromagnetic field envelope but also on the ellipticity of polarization of the radiation at the same point. (c) 2004 MAIK "Nauka/Interperiodica".     

Controlling the speed of electromagnetic waves in TbMnO3 in the sinusoidal antiferromagnetic phase by means of an external magnetic field

The possibility of controlling the speed of electromagnetic waves in TbMnO₃ of sinusoidal electromagnetic structure is investigated. Expressions for the components of the susceptibility tensors are obtained. Frequency dependences of the speed of electromagnetic waves are calculated for different values of an external magnetic field.     

States of electromagnetic field with specified charge motion in the Gupta and Fermi quantizations

Presented at the International Workshop on Squeezed and Correlated States, Moscow, December 3–7, 1990.     

Relativistic motion of a charged particle driven by an ellipticallypolarized electromagnetic wave propagating along a static magnetic field

The relativistic equations of motion of the interaction of a charged particle with an electromagnetic wave of elliptic polarization propagating along the direction of an external and constant magnetic field are solved in exact form. The method of solution is straight forward and allows to recover results previously reported in the literature     

Self-consistent equations for the interaction of an atom with an electromagnetic field of arbitrary intensity

A system of equations is suggested for the interaction of an atom with an electromagnetic field of arbitrary intensity. The distinctive feature of the equations is that, in the absence of the field, the electron density in the atom is determined by the Schrödinger equation and, in the presence of the field, by the equation resembling the classical equation for an electron in the Lorentz force field.