English
Related papers

Related papers: Chaos in nanomagnet via feedback current

200 papers

We study the dynamics of the spiral magnet under the charge current by solving the Landau-Lifshitz-Gilbert equation numerically. In the steady state, the current ${\vec j}$ induces (i) the parallel shift of the spiral pattern with velocity…

Strongly Correlated Electrons · Physics 2008-07-21 Kohei Goto , Hosho Katsura , Naoto Nagaosa

The synchronized magnetization dynamics in ferromagnets on a nonmagnetic heavy metal caused by the spin Hall effect is investigated theoretically. The direct and inverse spin Hall effects near the ferromagnetic/nonmagnetic interface…

Mesoscale and Nanoscale Physics · Physics 2017-03-22 Tomohiro Taniguchi

The destruction of a chaotic attractor leading to rough changes in the dynamics of a dynamical system is studied. Local bifurcations are characterised by a single or a pair of characteristic exponents crossing the imaginary axis. The…

Chaotic Dynamics · Physics 2020-11-16 Alexis Tantet , Valerio Lucarini , Frank Lunkeit , Henk A. Dijkstra

Phenomenological approach is developed in the theory of spin-valve type ferromagnetic junctions to describe exchange switching by current flowing perpendicular to interfaces. Forward and backward current switching effects are described and…

Materials Science · Physics 2007-05-23 E. M. Epshtein , Yu. V. Gulyaev , P. E. Zilberman

The switching of magnetic layers is studied under the action of a spin current in a ferromagnetic metal/non-magnetic metal/ferromagnetic metal spin valve. We find that the main contribution to the switching comes from the non-equilibrium…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 C. Heide , P. E. Zilberman , R. J. Elliott

Energy-efficient switching of magnetization is a central problem in nonvolatile magnetic storage and magnetic neuromorphic computing. In the past two decades, several efficient methods of magnetic switching were demonstrated including spin…

We obtain a fundamental instability of the magnetization-switching fronts in super-paramagnetic and ferromagnetic materials such as crystals of nanomagnets, ferromagnetic nanowires, and systems of quantum dots with large spin. We develop…

Mesoscale and Nanoscale Physics · Physics 2015-06-23 O. Jukimenko , C. M. Dion , M. Marklund , V. Bychkov

Spin-transfer is a typical spintronics effect that allows a ferromagnetic layer to be switched by spin-injection. Most of the experimental results about spin transfer are described on the basis of the Landau-Lifshitz-Gilbert equation of the…

Materials Science · Physics 2015-06-25 J. -E. Wegrowe , C. Ciornei , H. -J. Drouhin

The Landau-Lifshitz-Gilbert (LLG) equation, used to model magneto-dynamics in ferromagnets, tacitly assumes that the angular momentum associated with spin precession can relax instantaneously when the real or effective magnetic field…

Mesoscale and Nanoscale Physics · Physics 2021-07-20 Rahnuma Rahman , Supriyo Bandyopadhyay

Numerical solutions of the Landau-Lifshitz-Gilbert micromagnetic model incorporating thermal fluctuations and dipole-dipole interactions (calculated by the Fast Multipole Method) are presented for systems composed of nanoscale iron pillars…

Materials Science · Physics 2009-11-07 Gregory Brown , M. A. Novotny , Per Arne Rikvold

A theoretical study of delayed feedback in spin-torque nano-oscillators is presented. A macrospin geometry is considered, where self-sustained oscillations are made possible by spin transfer torques associated with spin currents flowing…

Mesoscale and Nanoscale Physics · Physics 2019-03-13 Jérôme Williame , Artur Difini Accioly , Damien Rontani , Marc Sciamanna , Joo-Von Kim

The shape of ferromagnetic resonance spectra of highly dispersed, chemically disordered Fe_{0.2}Pt_{0.8} nanospheres is perfectly described by the solution of the Landau-Lifshitz-Gilbert (LLG) equation excluding effects by crystalline…

Other Condensed Matter · Physics 2009-11-13 Jürgen Kötzler , Detlef Görlitz , Frank Wiekhorst

We investigate supercurrent-induced magnetization dynamics in a Josephson junction with two misaligned ferromagnetic layers, and demonstrate a variety of effects by solving numerically the Landau-Lifshitz-Gilbert equation. In particular, we…

Superconductivity · Physics 2015-05-19 Jacob Linder , Takehito Yokoyama

The Landau-Lifshitz equation is a coupled set of nonlinear partial differential equations that describes the dynamics of magnetization in a ferromagnet. This equation has an infinite number of stable equilibria. Steering the system from one…

Analysis of PDEs · Mathematics 2016-05-31 Amenda Chow , Kirsten A. Morris

The dynamics of magnetization near a stable equilibrium in ferromagnetic nanomagnets are examined within the Landau--Lifshitz--Gilbert (LLG) framework. For a small angle precession, the dependence of ferromagnetic resonance (FMR) frequency,…

The Landau-Lifshitz equation describes the behaviour of magnetization inside a ferromagnetic object. It is known that the Landau-Lifshitz equation has an infinite number of stable equilibrium points. The existence of multiple stable…

Dynamical Systems · Mathematics 2015-09-21 Amenda Chow , Kirsten A. Morris

A spin-polarized current transfers its spin-angular momentum to a local magnetization, exciting current-induced magnetization dynamics. So far, most studies in this field have focused on the direct effect of spin transport on magnetization…

Materials Science · Physics 2015-06-16 Kyung-Jin Lee , M. D. Stiles , Hyun-Woo Lee , Jung-Hwan Moon , Kyoung-Whan Kim , Seo-Won Lee

Recently an irregular easy axis reorientation demonstrating the Kapitza pendulum features were observed in numerical simulations of nanomagnet coupled to the Josephson junction. To explain its origin we study the magnetization bifurcations…

Superconductivity · Physics 2022-09-28 M. Nashaat , M. Sameh , A. E. Botha , K. V. Kulikov , Yu. M. Shukrinov

A theoretical model based on the Landau-Lifshitz-Bloch equation is developed to study the spin-torque effect in ferrimagnets. Experimental findings, such as the temperature dependence, the peak in spin torque, and the angular-momentum…

Materials Science · Physics 2018-11-21 Zhifeng Zhu , Xuanyao Fong , Gengchiau Liang

Synchronization and chaos caused by alternating current and microwave field in a spin torque oscillator consisting of a perpendicularly magnetized free layer and an in-plane magnetized reference layer is comprehensively studied…

Mesoscale and Nanoscale Physics · Physics 2019-12-25 Terufumi Yamaguchi , Nozomi Akashi , Kohei Naka jima , Sumito Tsunegi , Hitoshi Kubota , Tomohiro Taniguchi