Enhancement of Magnetoelectric Effect in Compositionally Graded Ferroelectric/Ferromagnetic Pb(1−x)SrxTiO3/CoFe2O4 Nanocomposites

In this study, phase-field model is developed for ferroelectric/ferromagnetic nanocomposites, in which ferroelectric composition is spatially varied along the thickness of ferroelectric layers. The developed phase field model is applied to investigate the effect of composition gradient on magnetoelectric response of the multilayer nanocomposite. Stripe domain structures are observed in both ferroelectric and ferromagnetic layers, however the sizes of magnetic domains are larger than that of polarization ones. Particularly, the size of polarization domains and geometry of domain walls are altered according to the gradient of ferroelectric composition. The obtained results suggest that the larger the composition gradient is, the higher the magnetoelectric effect becomes. The enhancement of magnetoelectric effect is attributed to the concentration of energy in ferroelectric layer, which originates from the spatial variation of ferroelectric composition.

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A phase-field model of phase transitions and domain structures of NiCoMnIn metamagnetic alloys

Acta Materialia ◽

10.1016/j.actamat.2014.10.014 ◽

2015 ◽

Vol 83 ◽

pp. 333-340 ◽

Cited By ~ 20

Author(s):

H.B. Huang ◽

X.Q. Ma ◽

J.J. Wang ◽

Z.H. Liu ◽

W.Q. He ◽

...

Keyword(s):

Phase Transitions ◽

Phase Field ◽

Field Model ◽

Phase Field Model ◽

Domain Structures

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Phase transitions and domain structures of ferroelectric nanoparticles: Phase field model incorporating strong elastic and dielectric inhomogeneity

Acta Materialia ◽

10.1016/j.actamat.2013.08.055 ◽

2013 ◽

Vol 61 (20) ◽

pp. 7591-7603 ◽

Cited By ~ 93

Author(s):

J.J. Wang ◽

X.Q. Ma ◽

Q. Li ◽

J. Britson ◽

Long-Qing Chen

Keyword(s):

Phase Transitions ◽

Phase Field ◽

Field Model ◽

Phase Field Model ◽

Domain Structures

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Phase Field Simulation of Ferroelectric Single Crystals

Aerospace ◽

10.1115/imece2005-79622 ◽

2005 ◽

Cited By ~ 1

Author(s):

T. Liu ◽

C. S. Lynch

Keyword(s):

Phase Field ◽

Wall Motion ◽

Field Model ◽

Landau Equation ◽

Phase Field Model ◽

Domain Wall Motion ◽

Ferroelectric Materials ◽

Time Dependent ◽

Ginzburg Landau ◽

Domain Structures

Ferroelectric materials exhibit spontaneous polarization and domain structures below the Curie temperature. In this study a cubic to tetragonal phase transformation and the evolution of domain structures in ferroelectric crystals are simulated by using the time-dependent Ginzburg-Landau equation. The effects of electric boundary conditions on the formation of domain patterns and field induced polarization switching are discussed. The phase field model is used to simulate the formation of domain structures, domain wall motion and the macroscopic response of ferroelectric materials under external fields.

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Phase-field model of multiferroic composites: Domain structures of ferroelectric particles embedded in a ferromagnetic matrix

The Philosophical Magazine A Journal of Theoretical Experimental and Applied Physics ◽

10.1080/14786430903193266 ◽

2010 ◽

Vol 90 (1-4) ◽

pp. 125-140 ◽

Cited By ~ 23

Author(s):

P.P. Wu ◽

X.Q. Ma ◽

J.X. Zhang ◽

L.Q. Chen

Keyword(s):

Phase Field ◽

Field Model ◽

Phase Field Model ◽

Domain Structures

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Domain Structures and Phase Diagram in 2D Ferroelectrics Under Applied Biaxial Strains - Phase Field Simulations and Thermodynamic Calculations

MRS Proceedings ◽

10.1557/proc-881-cc6.2 ◽

2005 ◽

Vol 881 ◽

Author(s):

Jie Wang ◽

Yulan Li ◽

Long-Qing Chen ◽

Tong-Yi Zhang

Keyword(s):

Phase Diagram ◽

Phase Field ◽

Field Model ◽

Landau Equation ◽

Phase Field Model ◽

Ginzburg Landau ◽

Elastic Interactions ◽

Domain Structures ◽

Domain State ◽

Different Temperatures

Absract:The microscopic domain structures in 2D ferroelectrics under applied biaxial strains are investigated using a phase field model based on the time-dependent Ginzburg-Landau equation that takes both long-range electric and -elastic interactions into account. The stable polarization patterns are simulated at different temperatures and applied inequiaxial strains. The results show that the ferroelectrics transfer from multi-domain state to single-domain state when temperature surpasses a critical value. On the other hand, the macroscopic equilibrium polarization states are also studied through a nonlinear thermodynamic theory. The corresponding transition from a1, a2 state (p1 ≠ 0, P2 ≠ 0) to a1 state (p1 ≠0, P2 = 0) or a2 state (p2 ≠ 0, P2 = 0) is also found from the “strain-straintemperature” phase diagram, which is constructed by minimizing Helmholtz free energy.

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