0000000000282283

AUTHOR

Laurent Bellaiche

showing 3 related works from this author

Room-temperature paramagnetoelectric effect in magnetoelectric multiferroics Pb(Fe1/2Nb1/2)O3 and its solid solution with PbTiO3

2015

We have observed the magnetoelectric (ME) response at room temperature and above in high-resistive ceramics made of multiferroic Pb(Fe1/2Nb1/2)O3 (PFN) and PFN-based solid solution 0.91PFN-0.09PbTiO3 (PFN-PT). The value of the paramagnetoelectric (PME) coefficient shows a pronounced maximum near the ferroelectric-to-paraelectric phase transition temperature, T C, and then decreases sharply to zero for T > T C. The maximal PME coefficient in PFN is about 4 × 10−18 s/A. The theoretical description of the PME effect, within the framework of a Landau theory of phase transitions allowing for realistic temperature dependences of spontaneous polarization, dielectric and magnetic susceptibilities, …

Phase transitionMaterials scienceFOS: Physical sciences02 engineering and technologyDielectric01 natural sciencesCondensed Matter::Materials ScienceCondensed Matter::Superconductivity0103 physical sciencesGeneral Materials ScienceMultiferroicsCeramic010306 general physicsCondensed Matter - Materials ScienceCondensed matter physicsMechanical EngineeringMaterials Science (cond-mat.mtrl-sci)021001 nanoscience & nanotechnologyMagnetic susceptibilityLandau theoryMagnetic fieldMechanics of Materialsvisual_artvisual_art.visual_art_medium0210 nano-technologySolid solution
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Revisiting spin cycloids in multiferroic BiFeO3

2018

We revisit the inverse spin current model that has been previously used to explain the existence of magnetic cycloids in bulk multiferroic ${\mathrm{BiFeO}}_{3}$. Using a first-principles-based effective Hamiltonian method, and in combination with Monte Carlo simulations, we predict a magnetic phase diagram as a function of first- and second-nearest-neighbor interaction strength in the spin current model and show that, in contrast with previous understanding, both first and second nearest neighbors have to be taken into account to be in accordance with experimental findings, including the existence of type-1 and type-2 cycloids with, respectively, $[1\overline{1}0]$ and $[11\overline{2}]$ p…

PhysicsCondensed matter physicsMonte Carlo methodInverse02 engineering and technologyFunction (mathematics)021001 nanoscience & nanotechnology01 natural sciencesMagnetic field0103 physical sciencesMultiferroics010306 general physics0210 nano-technologyPhase diagramSign (mathematics)Spin-½Physical Review B
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Magnetic Interactions in BiFeO$_3$: a First-Principles Study

2018

First-principles calculations, in combination with the four-state energy mapping method, are performed to extract the magnetic interaction parameters of multiferroic ${\mathrm{BiFeO}}_{3}$. Such parameters include the symmetric exchange (SE) couplings and the Dzyaloshinskii-Moriya (DM) interactions up to second-nearest neighbors, as well as the single-ion anisotropy (SIA). All magnetic parameters are obtained not only for the $R3c$ structural ground state, but also for the $R3m$ and $R\overline{3}c$ phases in order to determine the effects of ferroelectricity and antiferrodistortion distortions, respectively, on these magnetic parameters. In particular, two different second-nearest-neighbor…

PhysicsCondensed Matter - Materials ScienceCondensed matter physicsMagnetismMaterials Science (cond-mat.mtrl-sci)FOS: Physical sciences02 engineering and technology021001 nanoscience & nanotechnology01 natural sciencesFerroelectricityMagnetizationsymbols.namesake0103 physical sciencessymbolsAntiferromagnetismMultiferroics010306 general physics0210 nano-technologyHamiltonian (quantum mechanics)Ground stateAnisotropy
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