Structural and magnetic properties of Co/Ag multilayers

\u3cp\u3eThe structural properties and growth of sputtered Co/Ag multilayers were studied with nuclear magnetic resonance. For samples with a nominal Co thickness of less than 10 Å the Co grows in three-dimensional islands. If the nominal Co thickness is larger than 10-Å continuous Co layers are formed. The relation of the structural properties with magnetization and magnetoresistance is discussed.\u3c/p\u3

Fabry-Perot line shape analysis on an expanding cascaded arc plasma in argon

Fabry-Perot line profile measurements have been used to obtain heavy particle temperatures and electron densities for as expanding cascaded arc plasma in argon. This was done for the argon 415.9 and 696.5 nm neutral lines as a function of the distance from the onset of the expansion. Temperatures in the range of 2000-12000 K were obtained. The electron density in the beginning of the expansion appeared to be 5.6*10/sup 21/ m/sup -3/. The 696.5 nm line profiles appeared to be asymmetric because of self-absorption by cool metastables around the plasma. The density and temperature of these metastables could be determined by fitting the measurements to a theoretical model, and appeared to be around 10/sup 17/ m/sup -3/ and around 3000 K, respectivel

Thermally assisted reversal of exchange biasing in NiO and FeMn based systems

The stability of the exchange bias field Heb has been studied for magnetron sputtered NiO/Ni66Co18Fe16 and Ni66Co18Fe16/FeMn bilayers. A forced antiparallel alignment of the ferromagnetic magnetization to Heb results in a gradual decrease of Heb as a function of time for NiO as well as FeMn based samples. The observed decrease of Heb increases with temperature and is interpreted as a thermally assisted reversal of magnetic domains in the antiferromagnetic layer

Magnetization of Fe3O4/MgO multilayers studied with Mössbauer spectroscopy

The magnetic behavior and structure of Fe3O4/MgO multilayers have been investigated with Mössbauer spectroscopy in field, magnetization measurements, and scanning tunneling microscopy. It is shown that detailed structural knowledge of the size of the structural domains and the width of the antiphase boundaries are indispensable in understanding the magnetization behavior of the films and the contradictory results reported in the literature

On the construction of an Fe3O4 based all-oxide spin-valve

The progress made in constructing an all-oxide spin valve based on the intrinsic, fully spin-polarized electron transport in Fe3O4 is discussed. Two possible oxidic spacer layers, MgO and Mn3O4, have been investigated. Interlayer coupling studies indicate that MgO is the more suitable spacer layer of the two. Thus far a limited magnetoresistive effect 0.4% is found in the all oxide, Fe3O4-based, spin-valves which we have made. Possible causes for this low magnetoresistive effect are discussed

Magnetite Fe3-deltaO4 : a stoichiometry and structure analysis of MBE grown thin films using NO2 as the oxidising source

Epitaxial single crystalline films of iron oxides have been grown on MgO(100) substrates by means of MBE. Natural Fe or 57Fe was evaporated from alumina crucibles, and oxidised simultaneously with a dosed flux of NO2. The resulting oxide layers have been characterised in situ with RHEED, LEED, XPS, and AES. RHEED intensity oscillations, observed during deposition of the oxides, indicate a layer-by-layer growth for all substrate temperatures between 373 and 673 K. A stoichiometry analysis with CEMS, performed ex situ, shows that it is straightforward to prepare both the stable magnetite Fe3O4 and the metastable maghemite Fe3-dO4 phases. Moreover, also al1 solid solutions in between these two extreme phases, i.e. Fe3-dO4 with

Growth of magnetic nanowires along freely selectable 〈hkl〉 crystal directions

The crystal orientation of a magnetic nanowire can strongly influence its properties, yet nanowire growth with directional control remains challenging. Here, the authors use glancing angle deposition and angle switching to grow iron cobalt nanowires in seven different <hkl> crystal directions