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Spin-polarized electron energy loss spectroscopy is used for examining the properties of spin waves in ultrathin Co films and Fe films on Cu(001) are discussed. The spin wave excitation is observed as a well-defined peak in the loss spectrum for ultrathin Co films on Cu(001).

The Fe/Cr/Fe trilayers are epitaxially grown on atomically flat GaAs(001). The superconducting quantum interference device measurements confirm the interpretation of the magneto-optical Kerr effect (MOKE) loops and demonstrate homogeneity and sharpness of the interfaces in the structures.

A new study uses a scanning tunneling microscope to measure ferromagnetic resonance excitation of spin waves in an yttrium-iron-garnet sample.

A study was conducted on the spreading of Fe, Co and Ni from a dot deposited onto a W(110) substrate. The results indicate that a Cu cap layer covering a dot and surface can change the fast spreading directions for all three metals to . Moreover, the structure in the alloy layer formed during the spreading process may have caused the cap layer induced spreading anisotropy.

X-ray magnetic circular dichroism photoelectron emission microscopy (XMCD-PEEM) is used for examining the magnetic domain patterns of epitaxial single-crystalline Co/FeMn bilayers and Co/Cu/FeMn trilayers. The coercivity declines with increasing Cu layer thickness in domain images of the Co layer acquired after the application of different external magnetic fields.

A simple experiment is described to demonstrate the different deflected shapes assumed by a cantilever due to a torque or a force acting on its end. An optical deflection technique is used to show that different shapes appear in the cantilever even if the torque or force causes an identical displacement of the cantilever end. [DOI: 10.1119/1.1399045]

Research into the electron transport and magnetoresistance in high quality crystalline epitaxial Fe(001) and Au(001) films and exchange coupled Au/Fe/Au/Fe/GaAs(001) trilayer structures is presented. It was found that the scattering at the outer interfaces was diffuse, in spite of the large atomic terraces at the Au/vacuum and Fe/GaAs interfaces.

Photoelectron emission microscopy is combined with soft x-ray magnetic circular dichroism (XMCD) absorption spectroscopy to obtain local element-resolved quantitative magnetic properties with microscopic resolution. The value of 0.7(sub (mu)B) in the second phase is consistent with an fcc Fe phase containing nonfreromgnetic layers underneath a ferromagnetic surface.

The giant magnetoresistance of crystalline Fe/Cu/Fe(001) epitaxial structures characterized by scanning tunneling microscopy are presented. The sheet resistance was best modeled using a low temperature mean free path of 25 nm in the Fe layer.

A study was conducted to analyze the influence of strain-induced volume anisotropy and surface anisotropy in the spin reorientation of Ni/Cu(100) ultrathin films. Surface morphology by low temperature deposition was examined. The experiments were carried out in an ultrahigh vacuum multichamber system that includes scanning tunneling microscopy and magneto-optical Kerr effect.

The surface magnetic properties during the layer-by-layer growth of Co films on Cu(001) were explored using magnetization induced optical second harmonic (SH) generation. Findings showed that the SH signal changes as a function of Co thickness and an oscillatory behavior of the SH asymmetry was seen with one monolayer period for the transverse Kerr-geometry and s-polarized incident light. These oscillations were attributed to the periodic change of the magnetic surface susceptibility due to the periodic variation of the number of step edge atoms during the growth of Co.

A highly sensitive optical deflection technique and magneto-optical Kerr-effect measurements were used to measure the thickness dependence of the magneto-elastic coupling intrinsic film stress B1 and the magnetic in-plane anisotropy K4 of Fe films on W(100). It was shown that the thickness dependence of B1 can be seen by considering a second order magneto-elastic coupling constant D = 1 GJ/m(super 3) as a strain dependent correction of B1.

We have performed magnetic domain imaging with spatial, temporal, and layer resolution using x-ray photoelectron emission microscopy. The element selectivity of x-ray magnetic circular dichroism allows the magnetization dynamics of the different magnetic layers in spin-valve-like FeNi/Cu/Co trilayers to be studied separately, using the time structure of synchrotron radiation. The unique possibilities of this technique have been used to study the influence of the intrinsic magnetic properties of the different layers on the magnetization dynamics and the interlayer magnetic coupling. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

In tetragonally distorted [Fe.sub.0.5][Co.sub.0.5] alloy films grown epitaxially on Pd(001), Ir(001) and Rh(001) substrates the crystal field has located the electronic states near the Fermi level ([E.sub.F]) with one being below [E.sub.F] and the other above [E.sub.F] with an energy separation smaller than in bulk nondistorted material. This has resulted in a strong uniaxial anisotropy and an easy magnetization axis perpendicular to the film plane up to the thickness up to which the films have remained tetragonally distorted.

Tetragonal distortion in [Fe.sub.0.5][Co.sub.0.5] alloy films grown epitaxially on Rh(001) substrates has resulted in an easy magnetization axis perpendicular to the film plane up to the thickness of 17 ML. The final covering of the [Fe.sub.0.5][Co.sub.0.5]/Rh/[Fe.sub.0.5][Co.sub.0.5]/Rh(001) structure with Rh has increased the switching field and the effect is described by a locally enhanced magnetization in the Rh/[Fe.sub.1-x][Co.sub.x] interfaces.

The measurement of complex hysteresis loops for single-crystalline magneto-tunnel junction (MTJ) structures combined with an artificial layer antiferromagnet pinning magnetization of one of the junction electrodes is described. The studies have shown how the magnetization reversal is manipulated in the external magnetic field applied along three different crystallographic orientations.

The structural and magnetic properties of Fe films epitaxially grown on Pd/Cu(001) by pulsed laser deposition are investigated. An enhanced magneto-optical response is related to the spin polarization of the Pd interlayer and the increased Curie temperature of the Fe/Pd/Cu(001) system is described by polarized Pd at low thickness.

Thermal deposition (TD) and pulsed laser deposition (PLD) methods are used for preparing GaAs/Fe(001) crystalline ultrathin films. The effective perpendicular demagnetizing fields in the PLD films have decreased when compared to the TD samples because of an increase in the interface uniaxial perpendicular anisotropy at the Fe/Au(001) interface.

Interdiffusion in the Fe/GaAs interface is analyzed using conversion electron Mossbauer spectroscopy. The findings show that an independent magnetization switching in the Fe electrodes is achieved by pinning the magnetization of the Fe-top electrode by antiferromagnetic coupling across a Cr spacer to another Fe film.

The magnetization states of 20-nm-thick rectangular Co thin-film elements are studied with micromagnetic modeling and x-ray magnetic circular dichroism photoemission electron microscopy. The results show that the abundance of the virgin states is largely determined by the magnetic energy densities of the elements.

Some ultrathin multilayer structures the proportionality of the longitudinal Kerr ellpticity signal to the magnetic film thickness does not take place. Instead thinner magnetic layers give even twice larger contributions than the thicker ones located a few monolayers deeper.

Spin-polarized scanning tunneling spectroscopy (Sp-STS) is used for examining the magnetic states of self-organized Fe islands on W(001). Results indicate the presence of single-domain state below a thickness of 6 nm and a diameter of 120 nm in Fe islands.

Numerical estimates of the properties of Fe nanostripes using a combination of first-principles calculations and a Heisenberg model are presented. The stripes are step decorations grown with molecular beam epitaxy (MBE), are 1-2 monolayers thick, and display perpendicular magnetization.

Monte-Carlo simulations have been used to investigate the magnetization reorientation in second-order perpendicular anisotropy approximation. There was found to be an influence of the second-order perpendicular anisotropy on the spin reorientation transition when K(sub eff) vanishes.

Epitaxial artificial FeCu alloy thin films have been prepared in the fcc L1(sub0) ordered phase, using pulsed laser deposition on Cu(100). Electronic and magnetic properties were studied, and Fe exhibited magnetic moments comparable to those of fcc Fe films. The ratio between orbital and spin contribution to Fe d moments are enhanced in FeCu with regard to Fe/Cu(100), amounting to 0.12.

We generate high-order harmonics at 4MHz by a long-cavity laser and demonstrate applications in time-of-flight photoemission spectroscopy. Our results suggest a straightforward, oscillator-only setup for HHG-based photoelectron spectroscopy and microscopy with high repetition rate.