Interaction of the Light Field with N Atoms Possessing Dipole-dipole Interaction

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Interaction of light filaments in air

This paper analytically investigates the interaction of light filaments generated by a femtosecond laser beam in air. It obtains the Hamiltonian of a total laser field and interaction force between two filaments with different phase shifts and crossing angles. The property of the interaction force, which leads the attraction or repulsion of filaments, is basically dependent on the phase shift between filaments. The crossing angle between two filaments can only determine the magnitude of the interaction force, but does not change the property of the force.     

Newtonian gravitational theory: Interaction with light

The interaction of light with the gravitational field of a mass point described by a Newtonian gravitational field theory gives the same gravitational red shift as accepted theory. The dual force which is an integral part of the classical field theory and which has been shown to give the same advance of the perihelion of the orbit as Einstein's General Theory of Relativity is also the reason that light is deflected in the neighborhood of a massive particle. The deflection predicted is slightly more than 10% larger than Einstein's value, but within the experimental error of observational data. The dual force and its effects must be taken seriously. Its role in electrodynamics and quantum mechanics is briefly discussed.     

原子间相互作用对双模原子激光压缩性质的影响

研究了由单模压缩相干态光场与Ξ型三能级原子玻色爱因斯坦凝聚体(BEC)相互作用系统中耦合输出的双模原子激光的压缩特性,重点讨论了玻色爱因斯坦凝聚体原子间相互作用对原子激光压缩性质的影响,并讨论了原子激光压缩对光场初始压缩因子的依赖关系。结果表明:由光场诱导的双模原子激光呈现周期性的压缩,原子间的相互作用和光场初始压缩因子对原子的压缩性质具有重要影响。原子间的相互作用影响原子激光压缩的振荡频率而不会影响其压缩深度,而初始光场的压缩因子则对原子激光压缩深度产生调制作用,且初始光场的压缩因子越大,则原子激光压缩的时间越短。     

V型三能级原子与非经典光场作用中光场特性的变化

研究了V型三能级原子BEC与双模压缩光场相互作用系统中,忽略原子间相互作用和考虑原子间相互作用时光场的正交压缩和光子数压缩。结果表明,光场的正交压缩依赖于压缩参数,而光子数压缩与压缩参数、光场信号强度有关,在一定条件下,两种压缩可同时存在。原子间相互作用影响两种压缩的涨落随时间变化的周期,以及正交分量涨落随时间变化的幅度,而对光子数压缩涨落随时间变化的幅度几乎无影响。     

多原子体系与单模光场的多光子相互作用

用狄克（Ｄｉｃｋｅ）态的缀饰原子态的方法，解出了多原子体系与单模光场的多光子相互作用下总体系的量子态随时间演化的精确解。进而又研究了原子体系的粒子数反转，光场的压缩度及反聚束效应随时间的演化。通过数值计算，发出了一些新的演化规律。     

Interaction of classical nonrelativistic identically charged particles in a strong pulsed light field

In this review we consider the effective interaction force of identically charged nonrelativistic particles (electrons, light and heavy atoms nuclei) in a strong pulsed laser field. It is shown that under certain conditions, the effective interaction force can become a force of attraction. This effect significantly changes the kinematics of the interaction between the particles and can lead to bound states.     

Anticorrelations in Nondegenerate Parametric Three-Wave Interaction

It is shown that the anticorrelations in the photon numbers of the signal and the idler wave, respectively, generated in parametric three-wave interaction under suitable conditions, violate an inequality well-known in classical communication theory. Hence, it must be concluded that these anticorrelations reflect a typical quantum mechanical feature of light. In fact, this nonclassical behaviour is responsible for the occurrence of photon antibunching in the superposition field made up of both the signal and the idler wave, as will be pointed out in some detail.     

Interaction of short laser pulses with biological structures

Focusing of light pulses emitted by a Q-switched laser, which have a duration of some nanoseconds, into a medium leads to laser-induced breakdown. The shockwaves produced by this propagate through the medium and can interact with inhomogeneities situated within the medium and consequently cause destruction. Because of the increasing interest in these short light pulses in the medical field the interaction of the shockwaves with biological tissue has been investigated. The observed results indicate the influence of two physical quantities of the shockwave: the peak pressure and the duration.     

Multiwave Interaction of Light in a Bismuth Silicon Oxide Crystal in an Applied Meander Electric Field

An analysis is made of photorefractive nonlinearity resulting from the interaction between the charge gratings formed in a bismuth silicate crystal in an applied meander electric field under illumination by a strong reference and two signal light beams. It is shown that the nonlinear cross interaction between the primary holographic gratings recorded in the crystal should be taken into account where the intensities of the reference and signal light beams differ from one another in magnitude (less than 300 times).__________Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 2, pp. 24–29, February, 2005.     

Tavis-Cummings模型中原子间偶极作用对光场性质的影响

研究了与单模真空场作用的Tavis-Cummings模型中,原子间偶极－偶极相互作用对辐射光的平均光子数、光子的反聚束效应及光场压缩性质的影响。     

SU（2）相干态场与二能级原子的非简并双光子相互作用

研究了双模ＳＵ（２）相干态场与腔中二能级原子的非简并双光子相互作用。用数值计算讨论了ＳＵ（２）光场的反关联特性对原子动力学行的影响及场的量子统计性质时间的演化。     

Interaction of surface plasmons with interference modes in thin-film nanostructures

In Au/As₂S₃ metal-semiconductor surface composite structures, anomalous absorption of light beyond the fundamental absorption edge of the semiconductor is observed. This absorption is caused by the interaction of the near field of surface plasmons in metal nanoparticles with interference (virtual) modes of the Fabry-Perot cavity formed by the semiconductor film.     

Interaction of counterpropagating few cycle light pulses in nonlinear dielectric media and radiation generation at combination frequencies in this process

The regularities of the interaction of counterpropagating optical pulses of only a few oscillations of the light field in nonlinear dielectric media are studied theoretically. The temporal structure of the pulse field, due to its interaction with the counterpropagating pulse, is shown to be varied such that the field zeros are the most shifted in time and its extreme values are not shifted. The center of mass of the spectral density is shifted to the short-wavelength region. The efficiency of these phenomena is determined by the energy of the counterpropagating pulse and does not depend on its duration and spectral composition. The possibility of wave generation at tripled and combination frequencies is demonstrated for the media whose size is less than the interaction region. The efficiency of this generation with respect to the phase mutual modulation is shown to be increasing with a decrease in the number of oscillations in colliding pulses.     

介观 Josephson 结与激发偶奇相干态的相互作用

本文研究介观 Josephson 结与激发偶奇相干态的相互作用。研究了存在非经典光场时介观 Josephson 结中超导电流的一些特性，诸如崩塌与复苏现象，流压台阶特性，直流分量涨落以及超导电流的量子相干等。结果显示，超导电流的涨落及期望值可呈现直流分量。结果还显示稳态超导电流量，超导电流涨落的直流分量以及超导电流直流分量的关联函数等皆与光场的相位有关。     

The Interaction of a N-Type Four Level Atom with the Electromagnetic Field for a Kerr Medium Induced Intensity-Dependent Coupling

The interaction of a N-type four-level atom with a single field in the presence of an intensity-dependent coupling in a nonlinear Kerr medium is investigated. The exact analytic solution is obtained in the case that the atom and electromagnetic field are initially in a higher excited state and a coherent state, respectively. It is then demonstrated that effects such as nonclassical light generation, degree of entanglement stabilization, Kerr medium nonclassical control, and squeezed light are can be more efficiently implemented within this four-level framework than in many competing procedures. Additionally, inversion, linear entropy, Mandel Q-parameter and normal squeezing dynamics are examined.     

Interaction of nonlinear resonances in cavity QED

Strong coupling of the internal and external degrees of freedom of a cold atom to each other and to the spatially periodic field of the standing light wave in a high-finesse cavity is responsible for the dynamic instability of the atomic center-of-mass motion. Due to a weak interaction of the internal nonlinear resonances in the standard model of cavity QED, a stochastic layer appears, whose width in the semiclassical approximation is estimated in terms of the main parameters of the system: atomic recoil frequency, mean number of excitations, and detuning from the resonance. As a result, the atomic motion in the absolutely regular potential has the fractal character, with long Lévy flights alternating with small chaotic oscillations in potential wells.     

Interaction of light with a dye-doped nematic liquid crystal

The interaction of linearly and circularly polarized beams with a nematic liquid crystal doped with light-absorbing dyes has been studied by light-diffraction and microprojection methods. It has been found that there is a threshold for the emergence of light-induced anisotropic structures, which, depending on the type of dye, can be axisymmetric or extended in a direction determined by the light field. Possible mechanisms leading to the formation of the anisotropic structures are discussed. Zh. éksp. Teor. Fiz. 111, 2059–2073 (June 1997)     

Interaction Dynamics of the External and Internal Degrees of Freedom of an Atom in the Resonant Field of a Standing Light Wave

The theory of the dynamic interaction of the external (translational) and internal (electronic) degrees of freedom of a twolevel atom in the field of a standing light wave in a perfect cavity of the Fabry–Perot type was developed. The theory describes the energy exchange between three subsystems, namely, translational, electronic, and field subsystems, as opposed to the theories of the parametric interaction (in the approximations of Raman–Nath and/or large resonance detuning) and of the atomic motion in free space. In the semiclassical approximation, the corresponding Heisenberg equations of motion were shown to form a closed Hamiltonian dynamic system with two degrees of freedom, namely, translational and collective electron–field degrees of freedom. This system is integrated in terms of the elliptic Jacobian functions in the resonance limit. The solutions obtained describe the effects of trapping of an atom in the periodic potential of the standing light wave, and its cooling and heating, as well as the effect of the dynamic Rabi oscillations. The latter is caused by the interaction of the internal and external atomic degrees of freedom through the radiation field.     

Influence of Interaction Retardation and Radiation Reaction on the Fano Resonance Efficiency in the System of Nanoparticles

The system of metallic nanospheroids in the field of monochromatic light wave under conditions of manifestation of the Fano resonance is considered. The dimensions of the nanospheroids are much smaller than the wavelength of the incident radiation, but distances between them can be arbitrary. An analysis is made of the influence of the interparticle interaction and the reaction field on the inhomogeneity of the energy distribution of the collective oscillations of electrons in the system (the Fano resonance efficiency). It is shown that both the retardation and the reaction field contribute to an increase in the resonance efficiency.