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We report an experimental study which focuses on the magneto-optic interaction between light and perpendicularlymagnetized ferromagnetic thin-film multilayers. In this study, samples containing multiple Co/Pt interfaces are measured via the polar Magneto-Optic Kerr Effect (MOKE).Thanks to a sample set with a continuous Co thickness variation, and single and double Co layered samples, interface and bulk contributions to the magneto-optic activity areseparately determined. Kerr rotation and ellipticity signals are recorded as a function of the Co thickness. The results are analyzed via a transfer matrix method that accounts for the standard optical and magneto-optic effects in multilayered thin-films. Bulk magneto-optic contribution of Co (QCo;bulk) that is in accordance with literature is consistently determined despite the use of thin-films. Interfacial Co (QCo;int:) and magnetized Pt (QPt) contributions are presented in terms of two models. Interface phenomena of the large spin-orbit coupling between Co and Pt and the proximity induced magnetization in Pt layer are represented in the models. The strength of interfacial magneto-optic activity is interpreted as an indicator of the relative interface quality among the samples.

This erratum includes three modifications to the original paper:2 • The units of RDW (y-axis) in Fig. 4 (in main text), Fig. S3 (in supplementary material), and Fig. S4 (in supplementary material) should be X instead of mX. • At the end of the right-top paragraph of page 3, a reference to the supplementary material should be added. .shunting through the Pt layer (see supplementary material). • The following section should be added to the supplementary material.

A sharp magnetic soliton can be created and propagated in a vertical ratchet structure based on magnetic layers with out-of-plane anisotropy using a combination of antiferromagnetic and ferromagnetic interlayer couplings. This allows the use of identical magnetic layers in the stack, which simplifies the implementation of the ratchet compared to schemes which use alternating layer thicknesses. The ratchet behavior is analyzed using an Ising-macrospin approximation and conditions are derived for the propagation of a soliton, which is demonstrated experimentally. Values extracted from the experimental data for the coercivities and interlayer couplings show significant variation, which demonstrates the robustness of the soliton propagation.

Real-time in situ optical measurements were performed during the oxidation of ultrathin Al layers with a view to study oxidation kinetics and provide process control. The optical technique combines high temporal and spatial resolution with submonolayer sensitivity. In situ x-ray photoelectron spectroscopy measurements on the same samples are in good agreement, confirming the accuracy and sensitivity of the technique. For all thicknesses studied, the initial oxidation is extremely rapid, with quasilogarithmic behavior over the whole time scale. This technique could be utilized to study a wide variety of in situ reactive processes.

Polycrystalline silicon on glass substrates was grown by a method based on the creation of nucleation sites using laser crystallization of amorphous silicon followed by thermal annealing at temperatures below 600 °C. Annealing induces the crystallization of the material around the seeds, eventually leading to coalescence of adjacent domains before spontaneous nucleation sets in. Micro‐Raman spectroscopy shows that the seeds experience a tensile stress, which causes a radial birefringence in the surrounding amorphous silicon, detected by optical anisotropy measurements. We conjecture that this stress facilitates the crystallization of the material around the seed upon thermal annealing.

We present a technique, microscopic reflectance difference spectroscopy (μRDS), for the measurement of optical anisotropy with sub‐micron resolution. The technique is applied to the determination of the in‐plane anisotropy of GaAs/AlAs multiple quantum well structures in a phase resolved way, both below and above the fundamental gap. Confinement and local field effects are discussed, and a comparison is made with microscopic calculations based on a tight‐binding Hamiltonian for the electronic states.

Co2MnSi films were recently reported to show a significant increase in current-perpendicular-to-plane-giant-magnetoresistance upon annealing. Here, nuclear magnetic resonance was used to study the impact of annealing on the structure of such films. Below 550¿°C, no long-range L2 1 -order is observed, while annealing above 550¿°C leads to the formation of the ideal L2 1 configuration, however, with a distinct degree of off-stoichiometry. Further evidence from restoring field measurements hints that interdiffusion may account for the drop in magnetoresistance observed for samples annealed above 600¿°C. These results show that optimizing films for spintronics involves the identification of the best annealing temperature, high enough for long-range order to emerge, but low enough to maintain smooth interfaces.

We report experimentally obtained magnetic domain wall (DW) velocities of current-assisted field-driven DW creep in perpendicularly magnetized Pt/Co/Pt. We have intentionally introduced an asymmetry in the stacks by using different thicknesses of the two Pt layers sandwiching the Co layer. Thereby, it is tested whether conflicting current-induced domain wall motion (CI-DWM) results may be intrinsically related to the basic layout and growth. We sketch a scenario which could be at the basis of contradicting reports in literature where the direction of CI-DWM conflicts with spin-torque-transfer theory, allowing the sign of the current-induced effect on DW motion to be tuned.

In order to explain a number of recent experimental observations of laser-induced femtosecond demagnetization in the large fluence limit, we discuss the consequences of a recently proposed nonlocal approach. A microscopic description of spin flip scattering is implemented in an effective three temperature model, including electronic heat diffusion. Effects of finite film thickness on the demagnetization transients are discussed. Our results show a clear saturation of the ultrafast demagnetization, in excellent agreement with experimental observations.

It is now commonly accepted that materials exhibiting high perpendicular magnetic anisotropy are excellent candidates for devices based on current-induced domain-wall (DW) motion. A major hindrance of these materials however, is that they exhibit strong DW pinning. Here we report a significant increase in the field-driven DW velocity in Pt(4 nm)/Co68B32(0.6 nm)/Pt(2 nm) layers patterned into 900 nm wide strips. We compare the DW velocity between Co and Co68B32 films and discuss the observed effects using the morphology of the films investigated by high-resolution transmission electron microscopy.

The influence of current pulses on the domain structure of a 2 µm wide wire composed of a soft out-of-plane magnetized magnetic material is studied by high spatial resolution nonintrusive magnetic imaging. The injection of current pulses (1012 A/m2) leads to stable magnetic states composed of two domains with opposite magnetization direction separated by a domain wall parallel to the wire. The direction of the magnetization in the domains is reversed back and forth by applying successive current pulses with opposite polarity. The formation and control of the domain states by the current is attributed to the effect of the Oersted field, which is calculated to be large enough to induce the switching.

Time resolved magneto-optical Kerr measurements are carried out to study the precessional dynamics of ferromagnetic thin films with out-of-plane anisotropy. A combined analysis of parameters, such as coercive fields, magnetic anisotropy, and Gilbert damping a, is reported. Using a macrospin approximation and the Landau-Lifshitz-Gilbert equation, the effective anisotropy and a are obtained. A large damping varying with the applied field as well as with the thickness of the ferromagnetic layer is reported. Simulations using a distribution in the effective anisotropy allow us to reproduce the field evolution of a. Moreover, its thickness dependence correlates with the spin pumping effect. © 2009 American Institute of Physics.

We report the change in inelastic electron tunneling spectra (IETS) for AlAl Ox CoFeBAl junctions when the structure of CoFeB at its interface with Al Ox is intentionally changed from quasiamorphous to highly textured fcc. While for the quasiamorphous interface there are signs of the size quantization of magnons, the spectra for the fcc interface show distinct excitations at bias voltages associated with known surface magnon modes in fcc Co. These results demonstrate that IETS can be used as a tool to probe distinct structural changes of the magnetic electrode in tunnel junctions. © 2007 American Institute of Physics.

We examine the role of Mn diffusion in the thermal stability of tunneling spin polarization P by directly measuring P of Al/AlOx/Co/FeMn and Al/AlOx/Co90Fe10/FeMn junctions using superconducting tunneling spectroscopy (STS). We confirm Mn diffusion in our junctions using x-ray photoelectron spectroscopy after an ultrahigh vacuum 500 °C anneal. Surprisingly, and in contrast to the current belief, no drop in P is observed using STS. Therefore, though Mn diffuses significantly, it cannot be solely responsible for the drop in tunneling magnetoresistance observed after postdeposition anneals above 300 °C. ©2005 American Institute of Physics

Second harmonic generation from magnetic materials is shown to lead to a nonlinear magneto‐optical Kerr effect that can be orders of magnitude larger than its linear equivalent. The origin of this effect can be found in the differences between the linear and nonlinear solutions of the optical wave equations and in the symmetry properties of the corresponding optical tensors. Applications for the study of magnetic surfaces, thin films, and multilayers will be discussed.