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A nonconventional finite element formalism is proposed to solve the dynamic Landau-Lifshitz-Gilbert micromagnetic equations. Two bidimensional test problems are treated to estimate the validity and the accuracy of this finite element approach. Index Terms--Finite element methods, Landau-Lifshitz-Gilbert equations, micromagnetism, numerical analysis.

Recent studies in three-dimensional spintronics propose that the Œrsted field plays a significant role in cylindrical nanowires. However, there is no direct report on its impact on magnetic textures. Here, we use time-resolved scanning transmission x-ray microscopy to image the dynamic response of magnetization in cylindrical Co30Ni70 nanowires subjected to nanosecond Œrsted field pulses. We observe the tilting of longitudinally magnetized domains toward the azimuthal Œrsted field direction and create a robust model to reproduce the differential magnetic contrasts and extract the angle of tilt. Furthermore, we report the compression and expansion, or breathing, of a Bloch-point domain wall that occurs when weak pulses with opposite signs are applied. We expect that this work lays the foundation for and provides an incentive to further studying complex and fascinating magnetization dynamics in nanowires, especially the predicted ultra-fast domain wall motion and associated spin wave emissions. [ABSTRACT FROM AUTHOR]

X-ray photoelectron emission microscopy in combination with x-ray magnetic circular dichroism is used for examining the effect of an applied magnetic field on Neel caps. The results have not shown any correlation between the value of the reversal field and geometrical features of the dots.

Self-organized arrays of laterally alternating (Fe, Ag) nanostripes with a period of 3.5 nm were fabricated on Mo(110)/[Al.sub.2][O.sub.3](1120) by sequential deposition of Fe and Ag on Mo(110). The arrays were found to display a strong in-plane uniaxial anisotropy along [001], the directions of the wires, resulting from a balance between dipolar, interface and magnetoelastic anisotropy.

Describes the after-effect measurements performed on arrays of isolated ultrathin monocrystalline disk-shaped iron dots with inplane magnetization. Advantages of magnetic after-effect measurements; Sample fabrication and basic properties; Experimental protocol for magnetic after-effect measurements.

We report the fabrication of self-organized arrays of Fe nanostripes with a lateral period of 3.5 nm by sequential deposition of Fe and Ag on Mo(110). The wires display a strong in-plane uniaxial magnetic anisotropy along their length and are superparamagnetic above TB=185±15 K. The large value of nucleation volumes, which is inferred from the analysis of the thermal dependence of coercivity below TB, suggests the existence of interactions between the wires. [ABSTRACT FROM AUTHOR]

Provides soft x-ray resonant magnetic reflectivity measurements of thin films and multilayers. How linear polarized photons were used in the measurement of the thin films and multilayers in a transverse geometry; Quantitative examination of the magnetic properties of thin films and multilayers.

We report several procedures for the robust nucleation of magnetic domain walls in cylindrical permalloy nanowires. Specific features of the magnetic force microscopy (MFM) contrast of such wires are discussed, to avoid the misinterpretation of the magnetization states. The domain walls moved under quasistatic magnetic fields in the range 0.1-10mT, as evidenced by MFM at remanence at different stages of their motion. [ABSTRACT FROM AUTHOR]

We investigate numerically the transverse versus vortex phase diagram of head-to-head domain walls in Co/Cu/Py spin valve nano-stripes (Py: permalloy), in which the Co layer is mostly single domain while the Py layer hosts the domain wall. The range of stability of the transverse wall is shifted towards larger thickness compared to single Py layers, due to a magnetostatic screening effect between the two layers. An approached analytical scaling law is derived, which reproduces faithfully the phase diagram. [ABSTRACT FROM AUTHOR]

La2Zr2O7 (LZO) formation of bulk powders and of films by chemical solution deposition (CSD) process have been studied using propionates. The treatment involved a one step cycle in the reducing forming gas (Ar-5%H2) to be compatible with Ni-5at%W RABITS. Large amount of residual carbon was found in LZO powders formed in these conditions (10 wt%). The volume fraction of the cube texture in LZO films on Ni-5at%W RABITS was found to be a function of the speed of the gas flown above sample. This phenomenon is discussed in considering the C deposited from the carbon-containing gases emitted during the pyrolysis of the precursor. Using proper conditions (950 °C and the speed of gas of 6.8 × 10−2 m/s), LZO films with good surface crystallinity could be obtained on Ni-5at%W RABITS as demonstrated by X-ray diffraction, electron backscattered diffraction and RHEED. The existence of residual carbon in oxide films is a common question to films deposited by CSD processes under reducing condition. [ABSTRACT FROM AUTHOR]

Magnetic properties of nanometer-thick Co films intercalated at the graphene/Ir(111) interface are investigated using spin-polarized low-energy electron microscopy and Auger electron spectroscopy. We show that the graphene top layer promotes perpendicular magnetic anisotropy in the Co film underneath, even for relatively thick intercalated deposits. The magnetic anisotropy energy is significantly larger for the graphene/Co interface than for the free Co surface. Hybridization of the graphene and Co electron orbitals is believed to be at the origin of the observed perpendicular magnetic anisotropy. [ABSTRACT FROM AUTHOR]

We have developed and characterized the structure and composition of nanometers-thick solid-solution epitaxial layers of (V,Nb) on sapphire [formula], displaying a continuous lateral gradient of composition from one to another pure element. Further covered with an ultrathin pseudomorphic layer of W, these provide a template for the fast combinatorial investigation of growth or physical properties depending of strain. [ABSTRACT FROM AUTHOR]

Ordered arrays of magnetic nanowires are commonly synthesized by electrodeposition in nanoporous alumina templates. Due to their dense packing, strong magnetostatic interactions prevent the manipulation of wires individually. Using atomic layer deposition we reduce the diameter of the pores prior to electrodeposition. This reduces magnetostatic interactions, yielding fully remanent hysteresis loops. This is a first step toward the use of such arrays for magnetic racetrack memories. [ABSTRACT FROM AUTHOR]

The authors have self-organized versatile magnetic nanowires, i.e., with variable period and adjustable magnetic anisotropy energy (MAE). First, using the kinetic roughening of W(110), uniaxial templates of trenches were grown on commercial sapphire wafers. Unlike most templates used for self-organization, those have a variable period; 4–12 nm are demonstrated here. Fe deposition then results in the formation of wires in the trenches. The magnitude of MAE could be engineered up or down by changing the capping layer or underlayer, in turn affecting the mean superparamagnetic temperature, raised to 175 K so far. [ABSTRACT FROM AUTHOR]

We have fabricated 5-nm-high Fe(110) stripes by self-organized (SO) growth on a slightly vicinal R(110)/Al[sub 2]O[sub 3](1120) surface (R=Mo,W). Remanence, coercivity, and domain patterns were observed at room temperature. This contrasts with conventional SO epitaxial systems, that are superparamagnetic or even nonmagnetic at RT due to their flatness. Our process should help to overcome superparamagnetism without compromise on the lateral size if SO systems are ever to be used in applications. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Magnetic domain walls (DWs) in nanostructures are low-dimensional objects that separate regions with uniform magnetisation. Since they can have different shapes and widths, DWs are an exciting playground for fundamental research, and became in the past years the subject of intense works, mainly focused on controlling, manipulating, and moving their internal magnetic configuration. In nanostrips with in-plane magnetisation, two DWs have been identified: in thin and narrow strips, transverse walls are energetically favored, while in thicker and wider strips vortex walls have lower energy. The associated phase diagram is now well established and often used to predict the low-energy magnetic configuration in a given magnetic nanostructure. However, besides the transverse and vortex walls, we find numerically that another type of wall exists in permalloy nanostrips. This third type of DW is characterised by a three-dimensional, flux closure micromagnetic structure with an unusual length and three internal degrees of freedom. Magnetic imaging on lithographically-patterned permalloy nanostrips confirms these predictions and shows that these DWs can be moved with an external magnetic field of about 1 mT. An extended phase diagram describing the regions of stability of all known types of DWs in permalloy nanostrips is provided. [ABSTRACT FROM AUTHOR]

A correction is presented for a graph in the article "Reduction of magnetostatic interactions in self-organized arrays of nickel nanowires using atomic layer deposition" which is in a 2011 issue of this journal.