Open Access. Powered by Scholars. Published by Universities.®
Materials Science and Engineering Commons™
Open Access. Powered by Scholars. Published by Universities.®
- Keyword
-
- Ab initio (1)
- Atomic chain (1)
- Bloch line (1)
- DFT (1)
- DIFFaX (1)
-
- Density functional theory (1)
- Density of states (1)
- Department of Materials Science and Engineering (1)
- Department of Physics (1)
- Endotaxial (1)
- Epitaxial (1)
- Ferroelectrics (1)
- First-Principles (1)
- Hot-deformation (1)
- Lithium Ion Battery Cathode (1)
- Magnetism. (1)
- Magneto domain wall (1)
- Microstructure (1)
- Nd-Fe-B (1)
- Origins of magnetism in nanostructures (1)
- Permanent magnetic material (1)
- Phase Field (1)
- Spin transfer torque (1)
- Spin-orbit torque (1)
- X-ray Diffraction (1)
- Γ-FeSi2 (1)
- Publication
- Publication Type
Articles 1 - 5 of 5
Full-Text Articles in Materials Science and Engineering
Origin Of Magnetism In Γ-Fesi 2 /Si(111) Nanostructures, Liwei D. Geng, Sahil Dhoka, Ilan Goldfarb, Ranjit Pati, Yongmei M. Jin
Origin Of Magnetism In Γ-Fesi 2 /Si(111) Nanostructures, Liwei D. Geng, Sahil Dhoka, Ilan Goldfarb, Ranjit Pati, Yongmei M. Jin
Michigan Tech Publications
Magnetism has recently been observed in nominally nonmagnetic iron disilicide in the form of epitaxial γ-FeSi2 nanostructures on Si(111) substrate. To explore the origin of the magnetism in γ-FeSi2/Si(111) nanostructures, we performed a systematic first-principles study based on density functional theory. Several possible factors, such as epitaxial strain, free surface, interface, and edge, were examined. The calculations show that among these factors, only the edge can lead to the magnetism in γ-FeSi2/Si(111) nanostructures. It is shown that magnetism exhibits a strong dependency on the local atomic structure of the edge. Furthermore, magnetism can be enhanced by creating multiple-step edges. In …
Magnetism In Γ-Fesi2 Nanostructures: A First Principles Study, Sahil Dhoka
Magnetism In Γ-Fesi2 Nanostructures: A First Principles Study, Sahil Dhoka
Dissertations, Master's Theses and Master's Reports
First-principles calculations are performed on γ-FeSi2 nanostructures grown on Si (111) and (001) substrate. An attempt to explain the origin of emergent magnetic properties of the metastable gamma phase of iron di-silicide (γ-FeSi2) is made, which show ferromagnetic behavior on nanoscale, unlike its possible bulk form. Many papers try to explain this magnetism from factors like bulk, epitaxial strain, interface, surface, edges, and corners but doesn’t provide an analytical study for these explanations. Density functional theory is used to analyze the magnetic effects of these factors. The results for the epitaxial structures show no magnetic behavior for …
Investigation Of The Resistance To Demagnetization In Bulk Rare-Earth Magnets Comprised Of Crystallographically-Aligned, Single-Domain Crystallites With Modified Intergranular Phase, Jie Li
Dissertations, Master's Theses and Master's Reports
The research presented in this dissertation investigates whether an increased coercivity of Neodymium-Iron-Boron (Nd2Fe14B) based bulk magnets at elevated temperature (160°C), which is now only obtainable by substituting ~7wt% dysprosium (Dy) for a portion of neodymium (Nd), can be achieved through specific microstructural modifications with decreased Dy concentrations. The approach is to reduce the size of individual crystallographically-aligned grains in the magnet so that each grain can only support a single magnetic domain and to simultaneously dilute the Nd-Fe inter-granular phase present in conventional magnets with a non-Fe-containing, Nd-rich phase (Nd-Cu alloy) in an attempt to partially magnetically isolate the …
Modeling And Simulation Of Microstructures, Mechanisms, And Diffraction Effects In Energy Materials: Ferroelectrics And Lithium Ion Battery Cathode Materials, Jie Zhou
Dissertations, Master's Theses and Master's Reports - Open
Ferroelectric materials, as a large family exploited for the application of sensors, transducers and random access memories, open up a remarkable ground both for fundamental science and industry. Dielectric and piezoelectric properties are of the most interest in ferroelectric materials, which motivate research to enhance ferroelectric properties based on various application purposes. Among the multitudinous candidates in ferroelectric family, pseudo binary solid solutions with ABO3 lattice structure attract special attention in virtue of their large strain response when applying external loading. Furthermore, existence of morphological phase boundary (MPB) on their phase diagrams shed light on tuning material compositions to …
Structures, Properties And Functionalities Of Magnetic Domain Walls In Thin Films, Nanowires And Atomic Chains: Micromagnetic And Ab Initio Studies, Liwei D. Geng
Dissertations, Master's Theses and Master's Reports - Open
Structures, properties and functionalities of magnetic domain walls in thin film, nanowires and atomic chains are studied by micromagnetic simulations and ab initio calculations in this dissertation. For magnetic domain walls in thin films, we computationally investigated the dynamics of one-dimensional domain wall line in ultrathin ferromagnetic film, and the exponent α = 1.24 ± 0.05 is obtained in the creep regime near depinning force, indicating the washboard potential model is supported by our simulations. Furthermore, the roughness, creep, depinning and flow of domain wall line with commonly existed substructures driven by magnetic field are also studied. Our simulation results …