Nanocrystalline Fe-Pt alloys: phase transformations
... ball milling of elemental Fe and Pt powders at liquid nitrogen temperature. The as-milled Fe-Pt alloys consist of ~ 100 µm sized particles constituted by randomly oriented grains having an average size in the range of 10-40 nm. Depending on the milling time, three major microstructure types have bee ...
... ball milling of elemental Fe and Pt powders at liquid nitrogen temperature. The as-milled Fe-Pt alloys consist of ~ 100 µm sized particles constituted by randomly oriented grains having an average size in the range of 10-40 nm. Depending on the milling time, three major microstructure types have bee ...
Single Nanoparticle Magnetism: Hysteresis of
... • How does the hysteresis loop of an individual nanoparticle - measured along different crystallographic directions - look like? In other words: what is the MAE of an individual particle? • How does the coercive field depend on size, temperature, shape and morphology? • What is the magnetization re ...
... • How does the hysteresis loop of an individual nanoparticle - measured along different crystallographic directions - look like? In other words: what is the MAE of an individual particle? • How does the coercive field depend on size, temperature, shape and morphology? • What is the magnetization re ...
PDF only - at www.arxiv.org.
... spintronics, for example, reading the spin states, and writing the polarization states to reverse the spin states by electric field, to overcome the high-writing energy in magnetic random-access memories. Considering that little attention has been paid to multiferroicity until recently, it now offer ...
... spintronics, for example, reading the spin states, and writing the polarization states to reverse the spin states by electric field, to overcome the high-writing energy in magnetic random-access memories. Considering that little attention has been paid to multiferroicity until recently, it now offer ...
Dynamics of exciton dissociation in donor- acceptor polymer heterojunctions
... where fk is a fixed (time-independent) distribution function (fk being 0, 1, or 2 depend on the initial state occupation of the kth level) that determines the occupation of the time-dependent wave functions, and nj (t) contains information concerning the redistribution of electrons among the instant ...
... where fk is a fixed (time-independent) distribution function (fk being 0, 1, or 2 depend on the initial state occupation of the kth level) that determines the occupation of the time-dependent wave functions, and nj (t) contains information concerning the redistribution of electrons among the instant ...
Material
... Thermal quenching is an important phenomenon in CVD diamond. If trap parameters are determined using the initial rise method of TSL analysis, the luminescence decay leads to an underestimation of these parameters. Indeed, a deviation of almost 30% is observed between activation energy values determi ...
... Thermal quenching is an important phenomenon in CVD diamond. If trap parameters are determined using the initial rise method of TSL analysis, the luminescence decay leads to an underestimation of these parameters. Indeed, a deviation of almost 30% is observed between activation energy values determi ...
Superconductivity
Superconductivity is a phenomenon of exactly zero electrical resistance and expulsion of magnetic fields occurring in certain materials when cooled below a characteristic critical temperature. It was discovered by Dutch physicist Heike Kamerlingh Onnes on April 8, 1911 in Leiden. Like ferromagnetism and atomic spectral lines, superconductivity is a quantum mechanical phenomenon. It is characterized by the Meissner effect, the complete ejection of magnetic field lines from the interior of the superconductor as it transitions into the superconducting state. The occurrence of the Meissner effect indicates that superconductivity cannot be understood simply as the idealization of perfect conductivity in classical physics.The electrical resistivity of a metallic conductor decreases gradually as temperature is lowered. In ordinary conductors, such as copper or silver, this decrease is limited by impurities and other defects. Even near absolute zero, a real sample of a normal conductor shows some resistance. In a superconductor, the resistance drops abruptly to zero when the material is cooled below its critical temperature. An electric current flowing through a loop of superconducting wire can persist indefinitely with no power source.In 1986, it was discovered that some cuprate-perovskite ceramic materials have a critical temperature above 90 K (−183 °C). Such a high transition temperature is theoretically impossible for a conventional superconductor, leading the materials to be termed high-temperature superconductors. Liquid nitrogen boils at 77 K, and superconduction at higher temperatures than this facilitates many experiments and applications that are less practical at lower temperatures.