arXiv subjects

Zidong Wang

Publications and source records attributed to Zidong Wang.

60 records · Page 4Linked to original sources

arXiv2016

Dynamic Response in a Finite Size Composite Multiferroic Thin Film

Composite multiferroics, heterostructures of ferromagnetic (FM) and ferroelectric (FE) materials, are characterized by a remarkable magnetoelectric effect at the interface. Previous work has supported the ferromagnetic structure with magnetic spins and the ferroelectric with pseudospins which act as electric dipoles in a microscopic model, coupled with a magnetoelectric interaction [J. Appl. Phys. 118, 124109 (2015)]. In this work, by solving the stochastic Landau-Lifshitz-Gilbert equation, the electric-field-induced magnetization switching in a twisted boundary condition has been studied, and a behavior of domain wall in the ferromagnetic structure is discussed.

cond-mat.mes-hall↗

arXiv2016

Driving Skyrmions on a Composite Multiferroic Lattice

Magnetic skyrmions and multiferroics are the most interesting objects in nanostructure science that have great potential in future spin-electronic technology. The study of the multiferroic skyrmions has attracted much interest in recent years. This paper reports on the magnetic skyrmions induced by an electric driving field on a composite multiferroic lattice. By using the spin dynamics method, we use a classical magnetic spin model and an electric pseudospin model, which are coupled by a strong magnetoelectric coupling in the dynamical simulations. Interestingly, we observe some skyrmion-like objects on the electric component during the switching process, which is due to the connection between the electric and the magnetic structures.

cond-mat.mes-hall↗

arXiv2015

Pseudo-Spin Based Dynamical Model for Polarisation Switching in Ferroelectrics

A microscopic view of the response of the electric dipoles to a dynamic external field in a ferroelectric (FE) chain has been studied by two spin dynamics methods. One is the prominent micromagnetic approach, and the other is the micromagnetic approach with a variable size of the pseudo-spin. The energy stored in the ferroelectric chain is described by the transverse Ising model (TIM) with electric pseudo-spins. The simulations are based on a modified Landau-Lifshitz-Gilbert (LLG) equation which is precession free. The results obtained are shown and compared with the result supplemented by Landau-Devonshire (L-D) theory in the Appendix.

cond-mat.mes-hall↗

arXiv2015

Magneto-Electric Effect for Multiferroic Thin Film by Monte Carlo Simulation

Magneto-electric effect in a multiferroic heterostructure film, i.e. a coupled ferromagnetic-ferroelectric thin film, has been investigated through the use of the Metropolis algorithm in Monte Carlo simulations. A classical Heisenberg model describes the energy stored in the ferromagnetic film, and we use a pseudo-spin model with a transverse Ising Hamiltonian to characterise the energy of electric dipoles in the ferroelectric film. The purpose of this article is to demonstrate the dynamic response of polarisation is driven by an external magnetic field, when there is a linear magneto-electric coupling at the interface between the ferromagnetic and ferroelectric components.

cond-mat.mes-hall↗

arXiv2015

Spin Dynamics in Driven Composite Multiferroics

A spin dynamics approach has been used to study the behavior of the magnetic spins and the electric pseudo-spins in a 1-D composite multiferroic chain with a linear magneto-electric coupling at the interface. The response is investigated with either external magnetic or electric fields driving the system. The spin dynamics is based on the Landau-Lifshitz-Gilbert equation. A Gaussian white noise is later added into the dynamic process to include the thermal effects. The interface requires a closer inspection of the magneto-electric effects. Thus, we construct a 2-D ladder model to describe the behavior of the magnetic spins and the electric pseudo-spins with different magneto-electric couplings.

cond-mat.mes-hall↗

arXiv2015

Spin Dynamics Simulation of the Magneto-Electric Effect in a Composite Multiferroic Chain

A composite multiferroic chain with an interfacial linear magneto-electric coupling is used to study the magnetic and electric responses to an external magnetic or electric field. The simulation uses continuous spin dynamics through the Landau-Lifshitz-Gilbert equations of the magnetic spin and the electric pseudo-spin. The results demonstrate an accurate description of the distribution of the magnetisation and polarisation are induced by applied electric and magnetic field, respectively.

cond-mat.mes-hall↗