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Title: Ferroelectric-ferromagnetic multilayers: A magnetoelectric heterostructure with high output charge signal

Multiferroic composites and heterostructures comprising ferroelectric and ferromagnetic materials exhibit room-temperature magnetoelectric (ME) effects greatly exceeding those of single-phase magnetoelectrics known to date. Since these effects are mediated by the interfacial coupling between ferroic constituents, the ME responses may be enhanced by increasing the density of interfaces and improving their quality. A promising material system providing these features is a ferroelectric-ferromagnetic multilayer with epitaxial interfaces. In this paper, we describe theoretically the strain-mediated direct ME effect exhibited by free-standing multilayers composed of single-crystalline ferroelectric nanolayers interleaved by conducting ferromagnetic slabs. Using a nonlinear thermodynamic approach allowing for specific mechanical boundary conditions of the problem, we first calculate the polarization states and dielectric properties of ferroelectric nanolayers in dependence on the lattice mismatch between ferroic constituents and their volume fractions. In these calculations, the ferromagnetic component is described by a model which combines linear elastic behavior with magnetic-field-dependent lattice parameters. Then the quasistatic ME polarization and voltage coefficients are evaluated using the theoretical strain sensitivity of ferroelectric polarization and measured effective piezomagnetic coefficients of ferromagnets. For Pb(Zr₀.₅Ti₀.₅)O₃-FeGaB and BaTiO₃-FeGaB multilayers, the ME coefficients are calculated numerically as a function of the FeGaB volume fraction and used to evaluate the output chargemore » and voltage signals. It is shown that the multilayer geometry of a ferroelectric-ferromagnetic nanocomposite opens the way for a drastic enhancement of the output charge signal. This feature makes biferroic multilayers advantageous for the development of ultrasensitive magnetic-field sensors for technical and biomedical applications.« less
Authors:
 [1] ;  [2] ;  [3]
  1. Laboratoire Structures, Propriétés et Modélisation des Solides, UMR CNRS—École Centrale Paris, 92295 Châtenay-Malabry (France)
  2. Nanoelektronik, Technische Fakultät, Christian-Albrechts-Universität zu Kiel, D-24143 Kiel (Germany)
  3. A. F. Ioffe Physical-Technical Institute and St. Petersburg State Polytechnical University, St. Petersburg, 194021 and 195251 (Russian Federation)
Publication Date:
OSTI Identifier:
22306009
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 116; Journal Issue: 11; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Publisher:
American Institute of Physics (AIP)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; BORON COMPLEXES; BOUNDARY CONDITIONS; CRYSTAL DEFECTS; DIELECTRIC PROPERTIES; ELECTRICAL PROPERTIES; FERROELECTRIC MATERIALS; FERROMAGNETIC MATERIALS; GALLIUM COMPOUNDS; IRON COMPOUNDS; LATTICE PARAMETERS; LAYERS; LEAD COMPOUNDS; MAGNETIC FIELDS; MAGNETIC PROPERTIES; MONOCRYSTALS; OXYGEN COMPOUNDS; POLARIZATION; TITANATES; ZIRCONATES