An Approach to Structural and Functional Modeling of the Surface Morphology of Materials Based on Fluorinated Polymers

Russian Journal of General Chemistry - Dynamic modeling of the polymodal morphological structure of the polymer surface, with modified polyethylene terephthalate as an example, was performed. In...     

Calculation of Total Cross Section for γγ→γZ Scattering at High Energy

The total cross sections of γγ→γZ process for γγ c.m.s. energy 91.2—2000GeV are presented. W loop contribution is dominating when γγ c.m.s. energy is larger than 140GeV. The total cross section has a maximum, 220 fb(|cosθ|33cm^－2·s^－1 in which case more than 6000 events for γγ→γZ would be observable. In principle this process provides a test of the non-abelian nature of the standard model, especially the anomalous triple and quartic W-boson vertices.     

γγ→γZ过程高能总截面的数值计算

给出了γγ→γZ过程,质心系总能量在91.2—2000GeV的总截面.结果表明在总能量大于140GeV时,W玻色子图的贡献比起费米子图的贡献要大,当总能量在750GeV左右,截面达到极大值220fb(|cosθ|33cm^－2·sec^－1,每年在总能量750GeV处可观察到6000多个γγ→γZ事例,用它可以进一步验证标准模型,特别是其中规范粒子的三顶角和四顶角相互作用.     

局域模(实的及虚的)的一种新表述

本文给出了一种新的表述局域模(实的及虚的)的方法。我们引入了变形豫解式的迹P(z).它仅在z平面的实轴上有奇异性,孤立极点对应于实局域模。将P(E+iη)向下解析延拓至第二黎曼面,则其复极点对应于虚的(或不稳定的)局域模。复极点的实部是不稳定局域模的能量,虚部是它寿命的倒数,自然地得到了寿命为正的限制。此能量与寿命符合于相应共振散射的能量与宽度。本文还讨论了实局域模与虚局域模之间的关系。最后,比较了P(z)的奇异性与态密度的变化,并进一步阐明了寿命为正的及负的解之间的差别。指出,一般说来,只有寿命为正的解当作用强度增加时会变成实的局域模,负寿命的解是不会的。     

Macroscopic pure state of light free of polarization noise

The preparation of completely nonpolarized light is seemingly easy; an everyday example is sunlight. The task is much more difficult if light has to be in a pure quantum state, as required by most quantum-technology applications. The pure quantum states of light obtained so far are either polarized or, in rare cases, manifest hidden polarization; even if their intensities are invariant to polarization transformations, higher-order moments are not. We experimentally demonstrate the preparation of the macroscopic singlet Bell state, which is pure, is completely nonpolarized, and has no polarization noise. Simultaneous fluctuation suppression in three Stokes observables below the shot-noise limit is demonstrated, opening perspectives for noiseless polarization measurements. The state is shown to be invariant to polarization transformations. This robust highly entangled isotropic state promises to fuel important applications in photonic quantum technologies.     

Generation of bright squeezed vacuum in the Karassiov states

We suggest an experimental procedure allowing one to prepare squeezed vacuum in a special type of generalized Bell states, first introduced by V.P. Karassiov. We present the first results on the experimental generation of such states and observation of their polarization properties.     

Two methods for detecting nonclassical correlations in parametric scattering of light

Two methods for studying nonclassical correlations at the output of a two-mode parametric amplifier—first, the measurement of normalized Glauber correlation functions and, second, the measurement of the variance of the photon-number difference in conjugate modes—are compared. It is shown theoretically and experimentally that the corresponding quantities, the normalized correlation function, and the noise reduction factor have significantly different dependences on the main system parameters such as the parametric gain, optical losses, photo-detector quantum efficiency, and the detected angular and frequency bands.     

Detection of two-mode compression and degree of entanglement in continuous variables in parametric scattering of light

Generation of “twin beams” (of light with two-mode compression) in single-pass optical parametric amplifier (a crystal with a nonzero quadratic susceptibility) is considered. Radiation at the output of the nonlinear crystal is essentially multimode, which raises the question about the effect of the detection volume on the extent of suppression of noise from the difference photocurrent of the detectors. In addition, the longitudinal as well as transverse size of the region in which parametric transformation takes place is of fundamental importance. It is shown that maximal suppression of noise from difference photocurrent requires a high degree of entanglement of two-photon light at the outlet of the parametric amplifier, which is defined by Federov et al. [Phys. Rev. A 77, 032336 (2008)] as the ratio of the intensity distribution width to the correlation function width. The detection volume should be chosen taking into account both these quantities. Various modes of single-pass generation of twin beams (noncollinear frequency-degenerate and collinear frequency-nondegenerate synchronism of type I, as well as collinear frequency-degenerate synchronism of type II) are considered in connection with the degree of entanglement.     

Biphoton light generation in polarization-frequency bell states

Four polarization-frequency Bell states are obtained experimentally for photon pairs (biphotons) emitted during spontaneous parametric scattering from continuous pumping in the collinear frequency-nondegenerate regime. The polarization properties of such states are investigated. It is shown that biphoton light in the singlet Bell state is not polarized in the second or fourth order in the field.