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Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 14 of 14 for “"Tunneling magnetoresistance"”.
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A study of surface roughness issues in magnetic tunnel junctions
This research focuses on the spin-dependent tunneling phenomenon in magnetic tunnel junction. Based on the free electron model, it is found that the tunneling magnetoresistance and the exchange coupling are greatly modified by introducing the interface roughness into the basic …
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Designing a Method for Measuring Magnetoresistance of Nanostructures
… program is to produce nanosized magnetic tunneling junctions, and to study the physical properties of such devices. The physical phenomena of nanosized tunneling junctions are significantly different than that of currently popular micro-sized junctions. There is a considerable amount of …
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Magnetotransport effects in lateral and vertical ferromagnetic semiconductor junctions
This work is an investigation of giant magnetoresistance (GMR), tunneling magnetoresistance (TMR) and tunneling anisotropic magnetoresistance (TAMR)effects in (Ga,Mn) based ferromagnetic semiconductor junctions. Detailed results are published in the following articles: [1] C. Rüster, T. Borzenko, …
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Spin dependent transport in continuous and discontinuous CoFeB/MgO heterostructures
… of MgO. This model studied the variations in tunneling transmission due to inhomogeneity of the barrier. The results show a decrease of the density of the hotspots with the thickness of MgO barrier and that a perfectly insulating barrier is obtained at 1 nm thickness. For the study of the …
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Magnetic Weyl Semimetals for Spintronic Applications
… magnetic dynamics of Mn₃X and the spin-polarized tunneling in Co₂MnGa based spintronic devices remain not fully explored. In this thesis, I establish a theoretical framework to describe the low energy dynamics of strained Mn₃X. Using perturbation theory, I identify three distinct dynamic modes and …
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Landauer's theory of charge and spin transport in magnetic multilayers
… this thesis) including phenomena such as giant magnetoresistance (GMR), tunneling magnetoresistance (TMR) and current induced switching of magnetization. We then describe how to calculate the local charge and spin current in the direction perpendicular to the layers of an arbitrary magnetic …
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Spin-gap materials from first principles: properties and applications of half-metallic ferromagnets
… of possible applications of half-metals in giant magnetoresistance (GMR) and tunneling magnetoresistance (TMR) junctions, concluding that in the TMR case interface states can completely compensate the half-metallic property rendering it useless. A possible application of zincblende half-metals in …
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Nanomagnetismus von epitaktischen Fe(110)- und CrO 2 (100)-Strukturen im Hinblick auf potentielle spinelektronische Anwendungen
… via x-ray diffraction, atomic force and scanning tunneling microscopy, SQUID magnetometry, magnetooptical Kerr measurements, and spin resolved photoelectron spectroscopy, the surface roughness of the films has been drastically reduced. It is shown that the so prepared films exhibit a high spin …
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Magnetische Anisotropie und Spintransport in magnetoelektronischen Schichtsystemen und Nanostrukturen
… devices from pre-deposited multilayer samples. Tunneling magnetoresistance (TMR) structures based on ferromagnet/insulator/ferromagnet layer systems were prepared which showed a TMR ratio of up to 45% at room temperature.The second process developed in this work allows the fabrication of cpp …
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Study on graphene-based nanocomposites with special magnetoresistance properties
Magnetoresistance (MR) refers to the change of a material’s electrical resistance under the presence of an external magnetic field. The discovery of new MR phenomena (e.g., giant magnetoresistance (GMR) and tunneling magnetoresistance (TMR)) since the 1980s initiates the revolution of novel …
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Novel materials for magnetic tunnel junctions
… devoted to the understanding of spin polarized tunneling in magnetic tunnel junctions (MTJs). MTJs consist of two ferromagnetic layers separated by a thin (~2nm) insulating layer, usually amorphous Al2O3. The resistance of the structure depends on the relative orientation of the magnetizations …
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Wachstum und Charakterisierung des Tunnelmagnetowiderstand-Mehrschichtsystems Co-Al 2 O 3 -CoAl und das Studium spinfrustrierter Vortices in Ringstrukturen
… in a CsCl-type structure. The scanning tunneling microscopy (STM) image displays flat and large terraces with a width of 40-100 nm separated by steps with a height of 0.28 nm. This agrees with the lattice constant of CoAl and represents a double atomic step of the CsCl structure. The …
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A contactless and non-intrusive current measurement technique for low and medium voltage AC power systems
… contactless current measurement using Tunneling magnetoresistive (TMR) sensors is proposed and implemented for AC power systems. The proposed sensors overcome the aforementioned drawbacks of the CTs and provide more accurate outputs for asymmetrical currents during fault conditions. A …
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XPS and transport studies of oxide barriers in tunnel magnetoresistance junctions
… junctions were fabricated and their tunneling characteristics studied. Of special interest were the bias dependence and temperature dependence of the tunnel conductance and the TMR ratio. These were analyzed with fairly good success in terms of the Glazmann-Matveev model of inelastic …