The Experts below are selected from a list of 225 Experts worldwide ranked by ideXlab platform

Peter G Wolynes - One of the best experts on this subject based on the ideXlab platform.

  • Dynamical Theory of shear bands in structural glasses
    Proceedings of the National Academy of Sciences of the United States of America, 2017
    Co-Authors: Apiwat Wisitsorasak, Peter G Wolynes
    Abstract:

    The heterogeneous elastoplastic deformation of structural glasses is explored using the framework of the random first-order transition Theory of the glass transition along with an extended mode-coupling Theory that includes activated events. The Theory involves coupling the continuum elastic Theory of strain transport with mobility generation and transport as described in the Theory of glass aging and rejuvenation. Fluctuations that arise from the generation and transport of mobility, fictive temperature, and stress are treated explicitly. We examine the nonlinear flow of a glass under deformation at finite strain rate. The interplay among the fluctuating fields leads to the spatially heterogeneous dislocation of the particles in the glass, i.e., the appearance of shear bands of the type observed in metallic glasses deforming under mechanical stress.

Apiwat Wisitsorasak - One of the best experts on this subject based on the ideXlab platform.

  • Dynamical Theory of shear bands in structural glasses
    Proceedings of the National Academy of Sciences of the United States of America, 2017
    Co-Authors: Apiwat Wisitsorasak, Peter G Wolynes
    Abstract:

    The heterogeneous elastoplastic deformation of structural glasses is explored using the framework of the random first-order transition Theory of the glass transition along with an extended mode-coupling Theory that includes activated events. The Theory involves coupling the continuum elastic Theory of strain transport with mobility generation and transport as described in the Theory of glass aging and rejuvenation. Fluctuations that arise from the generation and transport of mobility, fictive temperature, and stress are treated explicitly. We examine the nonlinear flow of a glass under deformation at finite strain rate. The interplay among the fluctuating fields leads to the spatially heterogeneous dislocation of the particles in the glass, i.e., the appearance of shear bands of the type observed in metallic glasses deforming under mechanical stress.

Aimo Winkelmann - One of the best experts on this subject based on the ideXlab platform.

  • principles of depth resolved kikuchi pattern simulation for electron backscatter diffraction
    Journal of Microscopy, 2010
    Co-Authors: Aimo Winkelmann
    Abstract:

    Summary This paper presents a tutorial discussion of the principles underlyingthedepth-dependentKikuchipatternformationof backscattered electrons in the scanning electron microscope. To illustrate the connections between various electron diffractionmethods,theformationofKikuchibandsinelectron backscatter diffraction in the scanning electron microscope and in transmission electron microscopy are compared with the help of simulations employing the Dynamical Theory of electron diffraction. The close relationship between backscattered electron diffraction and convergent beam electrondiffractionisilluminatedbyshowinghowbotheffects can be calculated within the same theoretical framework. The influence of the depth-dependence of diffuse electron scattering on the formation of the experimentally observed electron backscatter diffraction contrast and intensity is visualized by calculations of depth-resolved Kikuchi patterns.Comparisonofanexperimentalelectronbackscatter diffractionpatternwithsimulationsassumingseveraldifferent depth distributions shows that the depth-distribution of backscattered electrons needs to be taken into account in quantitative descriptions. This should make it possible to obtain more quantitative depth-dependent information from experimental electron backscatter diffraction patterns via

J P Guigay - One of the best experts on this subject based on the ideXlab platform.

  • A simple view of the spherical wave in Dynamical Theory.
    Acta Crystallographica Section A, 1999
    Co-Authors: J P Guigay
    Abstract:

    The results of the Kato spherical-wave approach to the Dynamical Theory for perfect crystals are obtained by a simple and straightforward method based on the multiple-scattering expansion.

  • Dynamical Theory of Neutron Scattering
    X-Ray and Neutron Dynamical Diffraction, 1996
    Co-Authors: Michel Schlenker, J P Guigay
    Abstract:

    The orders of magnitude for the basic quantities are similar in neutron and X-ray scattering. When the neutron’s spin 1/2 is irrelevant, i.e. in diffraction by non-magnetic crystals, the Dynamical Theory of X-ray scattering can be very simply transferred to neutrons. Original features related to the neutron spin (§ 2) appear in diffraction by magnetic crystals (§ 3). Novel possibilities also arise because the neutrons can be manipulated from outside through applied fields (§4).

Alekseevich Vladimir Savin - One of the best experts on this subject based on the ideXlab platform.

  • Bifurcation Scenario of the Davydov-Scott Self-Trapping Mode
    Europhysics Letters (EPL), 2007
    Co-Authors: A V Zolotaryuk, K H Spatschek, Alekseevich Vladimir Savin
    Abstract:

    The Dynamical Theory of a quantum quasi-particle moving in a deformable\nanharmonic chain is extended into the supersonic region. Besides\na supersonic self-trapping mode, which is a direct extension of the\nwell-known subsonic Davydov-Scott mode, two additional Dynamically\nstable transfer mechanisms have been discovered in this region: i)\nthe capture and transfer of the self-trapping state by a supersonic\nacoustic (lattice) soliton and ii) the pairing of two lattice solitons\nvia their interaction with a quasi-particle.

  • Supersonic mechanisms for charge and energy transfers in anharmonic molecular chains
    Physical Review B, 1996
    Co-Authors: A V Zolotaryuk, K H Spatschek, Alekseevich Vladimir Savin
    Abstract:

    The Dynamical Theory of a quantum quasiparticle moving in a deformable\nanharmonic chain is extended into the supersonic region. Besides\na supersonic self-trapping mode, which is a direct extension of the\nwell-known subsonic Davydov-Scott mode, two additional Dynamically\nstable transfer mechanisms have been discovered in this region: (i)\nthe capture and transfer of the self-trapping state by a supersonic\nacoustic (lattice) soliton and (ii) the pairing of two lattice solitons\nvia their interaction with a quasiparticle.