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G. Alvarez H. MontielM.P. Cruz A.C. DuránR. Zamorano 《Journal of Alloys and Compounds》2011,509(35):L331
An electron paramagnetic resonance (EPR) study in the polycrystalline magnetoelectric YCrO3 is carried out at X-band (8.8-9.8 GHz) in the 300-510 K temperature range. For all the temperatures, the EPR spectra show a single broad line attributable to Cr3+ (S = 3/2) ions. The onset of the ferro-paraelectric transition has been determined from the temperature dependence of three main parameters deduced from the EPR spectra: the peak-to-peak linewidth (ΔHpp), the integrated intensity (IEPR) and the g-factor; these parameters indicate a behavior in agreement with a diffuse phase transition. Low-field microwave absorption (LFMA) is used to give a further knowledge on this material; where this technique also gives evidence of the ferro-paraelectric transition. 相似文献
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We report on the magnetoelectric characterization of epitaxial CoFe2O4-BaTiO3 nanocomposites grown by rf sputtering on Nb-doped SrTiO3 (001). Multiferroicity of the material is corroborated with both, ferroelectric and ferromagnetic hysteresis loops. Magnetoelectric coupling is investigated via magnetocapacitance measurements; a change of the capacitance of about 2% is observed for an applied magnetic field of 8 T. The possible origins of this magnetocapacitance are discussed. 相似文献
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R.K. Zheng S.H. ChoyY. Wang H.L.W. ChanC.L. Choy H.S. Luo 《Journal of Alloys and Compounds》2011,509(14):4878-4881
We fabricated a magnetoelectric laminate structure consisting of a magnetostrictive Tb0.3Dy0.7Fe1.92 (Terfenol-D) plate bonded to a La0.7Ca0.15Sr0.15MnO3 (LCSMO)/0.67Pb(Mg1/3Nb2/3)O3-0.33PbTiO3 (PMN-PT) structure where a LCSMO film was epitaxially grown on a PMN-PT single crystal substrate. When a dc magnetic field is applied perpendicular to the film plane, the magnetoresistance of the LCSMO film in the paramagnetic (ferromagnetic) state for the LCSMO/PMN-PT/Terfenol-D structure is larger (smaller) than that for the LCSMO/PMN-PT structure without Terfenol-D. These effects are caused by the magnetostriction-induced in-plane compressive strain in the Terfenol-D, which are transferred to the PMN-PT substrate, leading to a reduction in the in-plane tensile strain of the epitaxial LCSMO film and thereby modifying the magnetoresistance of the film. 相似文献
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Yachin Ivry Colm Durkan Daping Chu James F. Scott 《Advanced functional materials》2014,24(35):5567-5574
Most ferroelectrics are also ferroelastics (hysteretic stress‐strain relationship and response to mechanical stresses). The interactions between ferroelastic twin walls and ferroelectric domain walls are complex and only partly understood, hindering the technological potential of these materials. Here we study via atomic force microscopy the pinning of 180‐degree ferroelectric domain walls in lead zirconate titanate (PZT). Our observations satisfy all three categories of ferroelectric‐ferroelastic domain interaction proposed by Bornarel, Lajzerowicz, and Legrand. 相似文献
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《Ceramics International》2020,46(11):18707-18715
The ceramic 0.75BiFeO3–BaFe1/2Nb1/2O3 (0.75BF–BaFN) exhibits enhanced magnetisation and polar order regions at room temperature. This study investigated the microscopic structure and the magnetic, ferroelectric, magneto-ferroelectric, and optical properties of 0.75BF–BaFN by conducting experiments and performing density functional theory (DFT) calculations. Evidence of weak amplitude R-type octahedral rotations was observed using transmission electron microscopy (TEM). X-ray diffraction (XRD) refinement revealed that the P1 space group more appropriately described the structure of 0.75BF–BaFN. The weak influence of the magnetic field H on the polarisation of 0.7BF–BaFN and 0.75BF–BaFN ceramics was investigated. A notable magnetic enhancement was observed in 0.75BF–BaFN ceramics with a saturation magnetisation of 0.19 μB per Fe. DFT calculations predicted that the stable magnetic configuration of 0.75BF–BaFN is a G-type antiferromagnetic (AFM) structure. This study found stronger magnetic interactions between first-neighbour Fe ions (Ja = 12 meV) compared to pure BiFeO3. With a significant remanent moment, strong exchange coupling, and magnetic field control of polarisation, 0.75BF–BaFN may facilitate the development of room temperature single-phase magnetoelectric components. 相似文献
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The influence of an additional La0.67Sr0.33MnO3 (LSMO) magnetic phase on the structural, ferromagnetic, ferroelectric, and magnetoelectric properties of Ba0.85Ca0.15Zr0.1Ti0.9O3 (BCZT) ferroelectric phase was studied for composites of (1-x)BCZT -xLSMO (x = 0, 25, 50, 75 and 100%). The ferroelectric BCZT sample showed a perovskite single phase formation with a tetragonal crystal structure of the P4mm space group, and the magnetic phase of LSMO presented a rhombohedral crystal structure of R3c space group as shown by XRD. The composite sample with 25% LSMO exhibited large ferroelectric and piezoelectric properties with remnant, saturation polarization, and coercive electric field Pr ~7.74 μC/cm2, Ps ~11.69 μC/cm2 and EC ~12.22 kV/cm with a piezoelectric coefficient d33 ~ 231 pC/N. The magnetic characterization for the composites showed that the sample containing 75% of LSMO revealed the highest remnant, saturation magnetization, and coercive field of Mr ~1.358 emu/g, Ms ~19.17 emu/g, and HC ~33.19 Oe, respectively. Moreover, it revealed the largest magnetoelectric coupling coefficient αME ~2.51 mV/cm.Oe with high coupling quality at a lower applied magnetic field. The results highlight the value of these composites as lead-free room temperature magnetoelectric sensors and actuators. 相似文献