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Konstantin Y Guslienko - One of the best experts on this subject based on the ideXlab platform.

  • steady one dimensional domain wall motion in biaxial ferromagnets mapping of the landau Lifshitz Equation to the sine gordon Equation
    Physical Review B, 2020
    Co-Authors: R Ramaeiroa, R M Otxoa, P E Roy, Konstantin Y Guslienko
    Abstract:

    Motivated by the difference between the dynamics of magnetization textures in ferromagnets and antiferromagnets, the Landau-Lifshitz Equation of motion is explored. A typical one-dimensional domain wall in a bulk ferromagnet with biaxial magnetic anisotropy is considered. In the framework of Walker-type solutions of steady-state ferromagnetic domain wall motion, the reduction of the nonlinear Landau-Lifshitz Equation to a Lorentz-invariant sine-Gordon Equation typical for antiferromagnets is formally possible for velocities lower than a critical velocity of the topological soliton. The velocity dependence of the domain wall energy and the domain wall width are expressed in the relativistic-like form in the limit of large ratio of the easy-plane/easy-axis anisotropy constants. It is shown that the mapping of the Landau-Lifshitz Equation of motion to the sine-Gordon Equation can be performed only by going beyond the steady-motion Walker-type solutions.

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

  • analytical solutions of landau Lifshitz Equation for precessional dynamics
    Physica B-condensed Matter, 2004
    Co-Authors: G Bertotti, I D Mayergoyz, C Serpico
    Abstract:

    Abstract A rigorous analysis of the precessional magnetization dynamics in uniformly magnetized particles and films is carried out by deriving exact analytic solutions of Landau–Lifshitz Equation. The magnetic body is assumed of ellipsoidal shape, the external field is constant in time and applied in the plane normal to the hard axis. The analytic integration of the Landau–Lifshitz Equation is based on the explicit knowledge of two integrals of motion for the magnetization dynamics and leads to closed form expressions for the magnetization in terms of Jacobi elliptic functions.

  • comparison of analytical solutions of landau Lifshitz Equation for damping and precessional switchings
    Journal of Applied Physics, 2003
    Co-Authors: G Bertotti, C Serpico, I D Mayergoyz, Mihai Dimian
    Abstract:

    The analytical solutions to the Landau–Lifshitz Equation for “damping” and “precessional” switchings of materials with uniaxial anisotropy are found. These solutions lead to the expressions for the switching times and critical fields. Comparison of these two distinct modes of switching is presented.

  • analytical solutions of landau Lifshitz Equation for precessional switching
    Journal of Applied Physics, 2003
    Co-Authors: C Serpico, I D Mayergoyz, G Bertotti
    Abstract:

    A rigorous analysis of the precessional switching dynamics in uniformly magnetized particles and films is presented. Magnetization dynamics are described by the Landau–Lifshitz Equation and the precessional switching is realized by applying a field pulse orthogonal to the easy axis of the particle or the film. The analysis of the switching process is based on the explicit knowledge of two integrals of motion for the magnetization dynamics and leads to closed form analytical expressions for the magnetization in terms of Jacobi elliptic functions. It is shown that switching can occur only beyond a critical field threshold. The analytical solutions are used to predict the magnetization trajectory and the switching time under external field pulses of different amplitudes and durations.

  • numerical technique for integration of the landau Lifshitz Equation
    Journal of Applied Physics, 2001
    Co-Authors: C Serpico, I D Mayergoyz, G Bertotti
    Abstract:

    In the article, a finite difference scheme for the numerical integration of the Landau–Lifshitz Equation is presented. The scheme is based on the application of the midpoint rule coupled with a suitable extrapolation formula. The important properties of the scheme are the conservation of magnetization magnitude, its linearity, its second order truncation error accuracy, and the absence of spatial coupling. The accuracy of the scheme has been extensively tested by comparing numerical solutions with exact analytical solutions and by applying the scheme to the analysis of magnetization dynamics in conducting thin films.

Yuri I Gorobets - One of the best experts on this subject based on the ideXlab platform.

A Di Piazza - One of the best experts on this subject based on the ideXlab platform.

  • radiation reaction effects on radiation pressure acceleration
    New Journal of Physics, 2010
    Co-Authors: Matteo Tamburini, A Di Piazza, F Pegoraro, Christoph H Keitel, A Macchi
    Abstract:

    Radiation reaction (RR) effects on the acceleration of a thin plasma foil by a superintense laser pulse in the radiation pressure-dominated regime are investigated theoretically. A simple suitable approximation of the Landau–Lifshitz Equation for the RR force and a novel leap-frog pusher for its inclusion in particle-in-cell simulations are provided. Simulations for both linear and circular polarization of the laser pulse are performed and compared. It is found that at intensities exceeding 1023 W cm− 2 the RR force strongly affects the dynamics for a linearly polarized laser pulse, reducing the maximum ion energy but also the width of the spectrum. In contrast, no significant effect is found for circularly polarized laser pulses whenever the laser pulse does not break through the foil.

  • radiation reaction effects on radiation pressure acceleration
    arXiv: Plasma Physics, 2010
    Co-Authors: Matteo Tamburini, A Di Piazza, F Pegoraro, Christoph H Keitel, A Macchi
    Abstract:

    Radiation reaction (RR) effects on the acceleration of a thin plasma foil by a superintense laser pulse in the radiation pressure dominated regime are investigated theoretically. A simple suitable approximation of the Landau-Lifshitz Equation for the RR force and a novel leapfrog pusher for its inclusion in particle-in-cell simulations are provided. Simulations for both linear and circular polarization of the laser pulse are performed and compared. It is found that at intensities exceeding $10^{23} \Wcm$ the radiation reaction force strongly affects the dynamics for a linearly polarized laser pulse, reducing the maximum ion energy but also the width of the spectrum. In contrast, no significant effect is found for circularly polarized laser pulses whenever the laser pulse does not break through the foil.

  • exact solution of the landau Lifshitz Equation in a plane wave
    Letters in Mathematical Physics, 2008
    Co-Authors: A Di Piazza
    Abstract:

    The Landau–Lifshitz (The Classical Theory of Fields. Elsevier, Oxford 1975) form of the Lorentz–Abraham–Dirac Equation in the presence of a plane wave of arbitrary shape and polarization is solved exactly and in closed form. The explicit solution is presented in the particular, paradigmatic cases of a constant crossed field and of a monochromatic wave with circular and with linear polarization.

  • exact solution of the landau Lifshitz Equation in a plane wave
    arXiv: Optics, 2008
    Co-Authors: A Di Piazza
    Abstract:

    The Landau-Lifshitz form of the Lorentz-Abraham-Dirac Equation in the presence of a plane wave of arbitrary shape and polarization is solved exactly and in closed form. The explicit solution is presented in the particular, paradigmatic cases of a constant crossed field and of a monochromatic wave with circular and with linear polarization.

C Serpico - One of the best experts on this subject based on the ideXlab platform.

  • theory of injection locking for large magnetization motion in spin transfer nano oscillators
    IEEE Transactions on Magnetics, 2009
    Co-Authors: C Serpico, M Daquino, I D Mayergoyz
    Abstract:

    We study magnetization dynamics in spin-transfer devices subject to DC and microwave injected currents. When the frequency of the injected current is sufficiently close to the self-oscillation frequency of the device, phase-locking occurs. This phenomenon is theoretically studied by using Landau-Lifshitz Equation with Slonczewski spin-torque term. By exploiting separation of time scales and using averaging technique, we derive Equations which are applicable to the study of phase-locking for arbitrary large magnetization motion. The stability diagram in the (detuning, ac current)-plane is determined and it is shown that phase locking is hysteretic at sufficiently large ac currents.

  • analytical solutions of landau Lifshitz Equation for precessional dynamics
    Physica B-condensed Matter, 2004
    Co-Authors: G Bertotti, I D Mayergoyz, C Serpico
    Abstract:

    Abstract A rigorous analysis of the precessional magnetization dynamics in uniformly magnetized particles and films is carried out by deriving exact analytic solutions of Landau–Lifshitz Equation. The magnetic body is assumed of ellipsoidal shape, the external field is constant in time and applied in the plane normal to the hard axis. The analytic integration of the Landau–Lifshitz Equation is based on the explicit knowledge of two integrals of motion for the magnetization dynamics and leads to closed form expressions for the magnetization in terms of Jacobi elliptic functions.

  • comparison of analytical solutions of landau Lifshitz Equation for damping and precessional switchings
    Journal of Applied Physics, 2003
    Co-Authors: G Bertotti, C Serpico, I D Mayergoyz, Mihai Dimian
    Abstract:

    The analytical solutions to the Landau–Lifshitz Equation for “damping” and “precessional” switchings of materials with uniaxial anisotropy are found. These solutions lead to the expressions for the switching times and critical fields. Comparison of these two distinct modes of switching is presented.

  • analytical solutions of landau Lifshitz Equation for precessional switching
    Journal of Applied Physics, 2003
    Co-Authors: C Serpico, I D Mayergoyz, G Bertotti
    Abstract:

    A rigorous analysis of the precessional switching dynamics in uniformly magnetized particles and films is presented. Magnetization dynamics are described by the Landau–Lifshitz Equation and the precessional switching is realized by applying a field pulse orthogonal to the easy axis of the particle or the film. The analysis of the switching process is based on the explicit knowledge of two integrals of motion for the magnetization dynamics and leads to closed form analytical expressions for the magnetization in terms of Jacobi elliptic functions. It is shown that switching can occur only beyond a critical field threshold. The analytical solutions are used to predict the magnetization trajectory and the switching time under external field pulses of different amplitudes and durations.

  • numerical technique for integration of the landau Lifshitz Equation
    Journal of Applied Physics, 2001
    Co-Authors: C Serpico, I D Mayergoyz, G Bertotti
    Abstract:

    In the article, a finite difference scheme for the numerical integration of the Landau–Lifshitz Equation is presented. The scheme is based on the application of the midpoint rule coupled with a suitable extrapolation formula. The important properties of the scheme are the conservation of magnetization magnitude, its linearity, its second order truncation error accuracy, and the absence of spatial coupling. The accuracy of the scheme has been extensively tested by comparing numerical solutions with exact analytical solutions and by applying the scheme to the analysis of magnetization dynamics in conducting thin films.