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Showing 1 to 9 of 9 for “"double exchange"”.
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Structural, magnetic and electric transport properties of metal substituted La₀.₇Sr₀.₃MnO₃
… are explained by the competition between the double exchange and super exchange interactions, local John-Teller distortion, the dilution of magnetic ordering by the formation of AF clusters, the change of electron carrier density and band structure, and complex interactions between electrons, …
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Study of colossal magnetoresistance and pressure effects in La2/3Ca1/3MnO2 thin films /
… a paramagnetic to a ferromagnetic state. The double exchange mechanism (DE) and the Jahn-Teller deformations play an important role in CMR effect. Applied pressure has a very similar effect as does an applied magnetic field, except, at low temperatures (T<Tc) the field suppresses the …
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Critical behavior and transport properties of lanthanum manganite
… unlike that of ordinary ferromagnets. In the double exchange picture proposed by Zener, magnetism is closely linked to the nature of the charge carriers. We postulate that the exchange energy changes with the mixing fraction of the two carrier populations. By modifying the Oguchi model with …
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Vertically-aligned Oxide Nanocomposite Films for Improved Ferroelectrics and Ferromagnetics
… by a strain induced transition from super-exchange to double exchange coupling in the material. Last but not least, the potential of scalability of VAN films was explored by using sputtering to grow VAN structures instead of the commonly-used PLD growth. BaTiO3–Sm2O3 was used as a primary …
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Study on structure, surface morphology, electrical and magnetic properties in monovalent doped Pr0.75Na0.25Mn1-xCrxO3 AND Nd0.75Na0.25Mn1-yCryO3 of magnetic ceramics
… similar to Mn4+ where it is possibly involved in double-exchange mechanism. X-ray diffraction analysis revealed the crystalline phase of all samples consists of essentially single phase and crystallized in an orthorhombic structure. The Cr doping were influence the lattice parameters and the unit …
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Orbital order in iron-based superconductors
… that form the local moments, the magnetic exchange constants acquire dramatically different values along the two in-plane directions. Second, the itinerant electrons also undergo a nematic transition, causing the anisotropy observed in various experiments. Finally, combining orbital order …
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Efficient Fock Space Configuration Interaction Approaches For Large Strongly Correlated Systems
… is applied to several molecules exhibiting double exchange behavior. Model Hamil- tonian parameters are extracted from energy gaps and found to be in qualitative agreement with experiment. Having shown the efficacy of this approach, we move on to optimization, using a diagrammatic approach …
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Heteroepitaxial Interfaces Modify Collective States in Complex Oxides
… order were discussed under the formalism of the double exchange interaction. By constructing DSLs with LaMnO3, SrMnO3 and CaMnO3, electronic properties in ordered pseudo alloys having average doping, x=⅓ was compared with random alloy La⅔Sr⅓MnO3 samples. Effects due to strain disorder and charge …
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New ways to tune the multi-functionality of oxide thin films for memory applications
… vacancies. Together these reduce the unwanted double exchange (DE) coupling. This is hard to realize in plain LBMO films which contain cation vacancies, and have several strain-relaxing LBMO phases which result in an enhanced Mn4+/Mn3+ ratio, and hence to DE coupling and metallicity. Besides, …