Now showing 1 - 4 of 4
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    On the Statics of Transverse Domain Walls in Ferromagnetic Nanostrips
    (01-06-2020)
    Dwivedi, Sharad
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    Singh, Yenshembam Priyobarta
    In this article, we investigate the static properties of the transverse domain wall in ferromagnetic nanostrip under the influence of a uniform transverse magnetic field. We perform the analysis under the framework of the Landau–Lifshitz–Gilbert equation, which describes the evolution of magnetization inside the ferromagnetic medium. More precisely, first, we establish the magnetization profile in the two faraway domains and then examine the static magnetization profile in the sole presence of the applied transverse magnetic field, both analytically and numerically. The obtained analytical results are in qualitatively good agreement with recent numerical simulations and experimental observations.
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    Publication
    On Dynamics of Current-Induced Static Wall Profiles in Ferromagnetic Nanowires Governed by the Rashba Field
    (01-03-2017)
    Dwivedi, Sharad
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    This article deals with the analytical study of propagation of static wall profiles in ferromagnetic nanowires under the effect of spin–orbit Rashba field. We consider the governing dynamics for the evolution of magnetization inside the ferromagnetic material as an extended version of Landau–Lifshitz–Gilbert–Slonczewski equation of micromagnetism. It comprises the nonlinear dissipation factors like dry-friction and viscous. We establish the threshold and Walker-type breakdown estimates of the external sources in the steady-regime and also illustrate the obtained results numerically.
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    Publication
    Field-driven Motion of Ferrofluids in Ferromagnetic Nanowire under the Influence of Inertial Effects
    (01-01-2015)
    Dwivedi, Sharad
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    In this article, we investigate the field-driven motion of magnetic fluids (ferrofluids) in ferromagnetic nanowire under the influence of its own inertia. We establish the results in the framework of modified Landau-Lifschitz-Gilbert equation of micromagnetism which comprise the nonlinear dissipation factors like dry-friction and viscous. We delineate the motion in both the dynamical regimes namely the steady-state and the precessional. In the end, the physical significance of the obtained results is discussed with an aid of numerical analysis.
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    Publication
    Domain wall motion in multiferroic nanostructures under the influence of spin-orbit torque and nonlinear dissipative effect
    (01-01-2022)
    Shahu, Chiranjeev K.
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    Dwivedi, Sharad
    This article analytically investigates the one-dimensional motion of magnetic domain walls along a thin magnetostrictive nanostrip in a trilayer stack. This study is done under the framework of the extended Landau-Lifshitz-Gilbert equation. We consider the effect of stresses generated by the piezoelectric actuator, spin-orbit interactions caused by structural inversion asymmetry (Rashba and Spin-Hall effects), and dry-friction dissipation responsible for the structural disorder in the ferromagnetic material. First, we derive an explicit analytical expression of the domain wall velocity in the steady-state regime by employing the traveling waves ansatz and realistic assumptions on the considered parameters. It is observed that the strength of magnetostriction, Rashba and Spin-Hall effects, and dry friction affect the depinning threshold and Walker-breakdown, which represent the boundaries of a steady dynamical regime. Next, we numerically illustrate the presented analytical results and find they are in qualitatively good agreement with recent observations reported in the literature.