Genealogical tree of Russian schools on Nonlinear Dynamics

One of the most prominent feature of research in Russia and the former Soviet Union is so-called scientific schools. It is a collaboration of researchers with a common scientific background working, as a rule, together in a specific city or even at an institution. The genealogical tree of scientific schools on nonlinear dynamics in Russia and the former Soviet Union is grown. We use these terminology in a broad sense including theory of dynamical systems and chaos and its applications in nonlinear physics. In most cases we connect two persons if one was an advisor of the Doctoral thesis of another one. It is an analogue of the Candidate of Science thesis in Russia. If the person had no official advisor or we dont know exactly who was an advisor, we fix that person who was known to be an informal teacher and has influenced on him/her very much.

The effect of normal metal layers in ferromagnetic Josephson junctions

Using the Usadel equation approach, we provide a compact formalism to calculate the critical current density of 21 different types of ferromagnetic (F) Josephson junctions containing insulating (I) and normal metal (N) layers in the weak link regions. In particular, we obtain that even a thin additional N layer may shift the 0-$pi$ transitions to larger or smaller values of the thickness $d_F$ of the ferromagnet, depending on its conducting properties. For certain values of $d_F$, a 0-$pi$ transition can even be achieved by changing only the N layer thickness. We use our model to fit experimental data of SIFS and SINFS tunnel junctions, where S is a superconducting electrode.

Gluon production in the Lipatov effective action formalism

Gluon production on two scattering centers is studied in the formalism of reggeized gluons. Different contributions to the inclusive cross-section are derived with the help of the Lipatov effective action. The AGK relations between these contributions are established. The found inclusive cross-section is compared to the one in the dipole picture and demonstrated to be the same.

Ferromagnetic planar Josephson junction with transparent interfaces: a {phi} junction proposal

We calculate the current phase relation of a planar Josephson junction with a ferromagnetic weak link located on top of a thin normal metal film. Following experimental observations we assume transparent superconductor-ferromagnet interfaces. This provides the best interlayer coupling and a low suppression of the superconducting correlations penetrating from the superconducting electrodes into the ferromagnetic layer. We show that this Josephson junction is a promising candidate for an experimental {phi} junction realization.

Detection of 107 glitches in 36 southern pulsars

Timing observations from the Parkes 64-m radio telescope for 165 pulsars between 1990 and 2011 have been searched for period glitches. A total of 107 glitches were identified in 36 pulsars, where 61 have previously been reported and 46 are new discoveries. Glitch parameters were measured by fitting the timing residual data. Observed relative glitch sizes Delta u_g/ u range between 10^-10 and 10^-5, where u = 1/P is the pulse frequency. We confirm that the distribution of Delta u_g/ u is bimodal with peaks at approximately 10^-9 and 10^-6. Glitches are mostly observed in pulsars with characteristic ages between 10^3 and 10^5 years, with large glitches mostly occurring in the younger pulsars. Exponential post-glitch recoveries were observed for 27 large glitches in 18 pulsars. The fraction Q of the glitch that recovers exponentially also has a bimodal distribution. Large glitches generally have low Q, typically a few per cent, but large Q values are observed in both large and small glitches. Observed time constants for exponential recoveries ranged between 10 and 300 days with some tendency for longer timescales in older pulsars. Shorter timescale recoveries may exist but were not revealed by our data which typically have observation intervals of 2 - 4 weeks. For most of the 36 pulsars with observed glitches, there is a persistent linear increase in dot u in the inter-glitch interval. Where an exponential recovery is also observed, the effects of this are superimposed on the linear increase in dot u. In some cases, the slope of the linear recovery changes at the time of a glitch. The ddot u values characterising the linear changes in dot u are almost always positive and, after subtracting the magnetospheric component of the braking, are approximately proportional to the ratio of |dot u| and the inter-glitch interval, as predicted by vortex-creep models.

Influence of e-e scattering on the temperature dependence of the resistance of a classical ballistic point contact in a two-dimensional electron system

We experimentally investigate the temperature (T) dependence of the resistance of a classical ballistic point contact (PC) in a two-dimensional electron system (2DES). The split-gate PC is realized in a high-quality AlGaAs/GaAs heterostructure. The PC resistance is found to drop by more than 10% as T is raised from 0.5 K to 4.2 K. In the absence of a magnetic field, the T dependence is roughly linear below 2 K and tends to saturate at higher T. Perpendicular magnetic fields on the order of a few 10 mT suppress the T-dependent contribution dR. This effect is more pronounced at lower temperatures, causing a crossover to a nearly parabolic T dependence in a magnetic field. The normalized magnetic field dependencies dR(B) permit an empiric single parameter scaling in a wide range of PC gate voltages. These observations give strong evidence for the influence of electron-electron (e-e) scattering on the resistance of ballistic PCs. Our results are in qualitative agreement with a recent theory of the e-e scattering based T dependence of the conductance of classical ballistic PCs [ Phys. Rev. Lett. 101 216807 (2008) and Phys. Rev. B 81 125316 (2010)].

Feynman Diagrams, Differential Reduction, and Hypergeometric Functions

We will present some (formal) arguments that any Feynman diagram can be understood as a particular case of a Horn-type multivariable hypergeometric function. The advantages and disadvantages of this type of approach to the evaluation of Feynman diagrams is discussed.

Hypergeometric functions, their epsilon expansions and Feynman diagrams

We review the hypergeometric function approach to Feynman diagrams. Special consideration is given to the construction of the Laurent expansion. As an illustration, we describe a collection of physically important one-loop vertex diagrams for which this approach is useful.

Observations of Spontaneous Raman Scattering in Silicon Slow-light Photonic Crystal Waveguides

We report the observations of spontaneous Raman scattering in silicon photonic crystal waveguides. Continuous-wave measurements of Stokes emission for both wavelength and power dependence is reported in single line-defect waveguides in hexagonal lattice photonic crystal silicon membranes. By utilizing the Bragg gap edge dispersion of the TM-like mode for pump enhancement and the TE-like fundamental mode-onset for Stokes enhancement, the Stokes emission was observed to increase by up to five times in the region of slow group velocity. The results show explicit nonlinear enhancement in a silicon photonic crystal slow-light waveguide device.

Efficient method to calculate total energies of large nanoclusters

We present an approach to calculate total energies of nanoclusters based on first principles estimates. For very large clusters the total energy can be separated into surface, edge and corner energies, in addition to bulk contributions. Using this separation and estimating these with direct, first principles calculations, together with the relevant chemical potentials, we have calculated the total energies of Cu and CdSe tetrahedrons containing a large number of atoms. In our work we consider polyhedral clusters so that in addition our work provides direct information on relaxation. For Cu the effects are very small and the clusters vary uniformly from very small to very large sizes. For CdSe there are important variations in surface and edge structures for specific sizes; nevertheless, the approach can be used to extrapolate to large non-stoichiometric clusters with polar surfaces.