Global ETD Search
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Showing 1 to 20 of 20 for “"magnetoelectric coupling"”.
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Magnetoelectric Coupling in BaTiO3-BiFeO3 Multilayers: Growth Optimization and Characterization
The presented thesis explores the magnetoelectric (ME) coupling in multiferroic thin film multilayers of BaTiO3 (BTO) and BiFeO3 (BFO). Multiferroics possess more than one ferroic order parameter, in this case ferroelectricity and anti-ferromagnetism. Cross-coupling between these otherwise separate …
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Anisotropic behaviour of magneto-electric coupling in multiferroic composites
The anisotropy of the direct magnetoelectric effect in textured nickel ferrite/lead zirconate titanate strain mediated bilayer composites has been studied. The magnetic layers of these samples have been crystallographically textured in planes of the form {100}, {110} and {111}. In this study, it is …
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Pulsed Laser Deposition of Thin Film Heterostructures
… microscopy it is possible to investigate the magnetoelectric coupling between the electrostrictive Lead Titanate and magnetostrictive Terfenol-D thin film. Upon examination of the produced thin films the phase and amplitude components of the piezoelectric signal experience changes in response …
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Structure, magnetism and multiferroicity in self-assembled oxide nanocomposites
… at interfaces, enhanced ferroelectricity and magnetoelectric coupling, which are often absent or occur at a lower magnitude in single phase materials. In particular, magnetoelectric multiferroics, materials that exhibit two or more ferroic orders (such as ferromagnetism and ferroelectricity) …
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Effect of nonstoichiometry on the magnetism and ferroelectricity of Fe- and Co-substituted strontium titanate thin films
Multiferroic and magnetoelectric materials, in which the magnetic properties can be controlled via electric field and vice versa, hold the potential to be useful in several emerging memory technologies, including spin-wave devices and multi-state memory. Room temperature ferromagnetism and …
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Templated self-assembly of multiferroic nanocomposites
… electron gases, enhanced ionic transport and magnetoelectric coupling, among many other. In this this thesis, we focus on self-assembled oxide nanocomposites, which elegantly organize into vertical nanostructures via spontaneous phase-separation, naturally forming numerous such …
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Interplay Between the Lattice and Spin Degrees of Freedom in Magnetoelectric and Magnetic Materials
… contains several investigations on the cross-coupling between structural and spin degrees of freedom in multiferroic and ferrimagnetic compounds by means of first-principles calculations and ab-initio-based Monte-Carlo simulations. We start with the reviews of magnetoelectricity, …
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Magnetoelectric Thin Film Heterostructures and Electric Field Manipulation of Magnetization
The coupling of magnetic and electric order parameters, i.e., the magnetoelectric effect, has been widely studied for its intriguing physical principles and potentially broad industrial applications. The important interactions between ferroic orderings -- ferromagnetism, ferroelectricity and …
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Effects of transition metal doping on multiferroic ordering in ni3v2o8 and fevo4
… </p> <p>In the case of FeVO4, we find that the magnetoelectric coupling in FeVO4 is remarkably robust to dopants with minimal suppression in transition temperatures for 3 transition metal dopants, Zn, Cr and Fe. We observe clear reversible polarization even at 20% doping suggesting the …
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Investigation into the Magnetoelectric Effect and Magnetic Properties of Iron-doped Cobalt Molybdate
The plausibility of revealing linear magnetoelectric coupling is investigated in the cobalt molybdate (Co2Mo3O8). Recently, Wang et al.[Scientific Reports. 2015;Vol. 5:Article 12268] showed that iron molybdate(Fe2Mo3O8) can be induced into a ferrimagnetic state from a nominal antiferromagnetic …
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Cation Site Occupancy and Defect Engineering in Perovskite Heterostructures
… materials for next-generation multiferroic and magnetoelectric devices. Cation and anion point defects collectively affect the structural, electrical, and magnetic properties of complex oxides. At the same time, such defects allow one to manipulate the behavior and tailor it to desired …
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Electro-Optic And Magneto-Dielectric Properties Of Multifunctional Nitride And Oxide Materials
… devices. For example, materials having a strong coupling between charge and spin degrees of freedom are essential to realizing a new class of devices referred to generally as spintronics. However, these multifunctional systems pose new scientific challenges in understanding the origin and …
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Spectroscopic study of emergent electronic phases in transition metal based compounds
… spin chirality and polar order. This intrinsic coupling between the magnetic and dipolar order parameters results in record-strength magnetoelectric effects. Two-dimensional materials possessing such intrinsic multiferroic properties have been long sought for harnessing magnetoelectric coupling …
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Direct and inverse electromagnetic scattering problems for bi-anisotropic periodic media
… three quantities: permittivity, permeability and magnetoelectric coupling coefficient. These are 3 × 3 matrix-valued functions of the spatial variable and make up two constitutive relations in addition to the Maxwell’s equations. In the equations, the incident fields which we send towards the …
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Magnetoelectric Properties of Epitaxial Spinel Oxide Thin Films
… are presented as well as the characterization of magnetoelectric coupling of the material. Secondly, another unique spinel, Cobalt Chromite, CoCr2O4 (CCO), which has a canted conical magnetic ordering and shows spontaneous polarization, is also studied in this thesis. The polarization and …
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modeling and application of nonlinear metasurface
… as negative refractive index, magneto-electric coupling‒provide novel nonlinear features not available in nature. Compared to conventional optical components that often extend many wavelengths in size, nonlinear metasurfaces are flexible and extremely compact. </p><p>Characterization of a …
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A Micromechanics Study on Ferroelectrics and Multiferroic Composites
… observations, the nonlinear electromechanical coupling responses of ferroelectrics are strongly depending on the frequency of the applied electric field. In order to interpret the influence of a frequency, an exponential function is introduced to express the remanent polarization and coercive …
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Tuning Strong Correlated Properties in EuTiO3 Thin Films Grown by Pulsed Laser Deposition
… perovskite oxides, control and tailor of strong coupling between structural degrees of freedom and correlated order parameters is required. One typical example of decently tuned functionalities in transition metal is perovskite EuTiO3 (ETO). This compound has attracted intensive attention for …
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Magnetoelectric Effect in Ferroelectric-Ferromagnetic Heterostructures
The magnetoelectric (ME) effect, a coupling effect between magnetic and electric orders, has been widely investigated, both from a fundamental science perspective and an applications point of view. Magnetoelectric composites with one piezoelectric phase and one magnetostrictive phase can be …
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Multipoles, Magnetic charges and chiral properties in antiferromagnetic materials inferred from resonant X-Ray diffraction
… super-exchange interactions and electron¿phonon coupling. Previous works from different groups have not been able to explain the resonant x-ray diffraction data collected at the neptunium M4-edge. But new information, related to a change in the symmetry of the neptunium sites (3 ¿m) due to the …