We review recent evidence indicating that researchers in experimental psychology may have used suboptimal estimates of word frequency. Word frequency measures should be based on a corpus of at least 20 million words that contains language participants in psychology experiments are likely to have been exposed to. In addition, the quality of word frequency measures should be ascertained by correlating them with behavioral word processing data. When we apply these criteria to the word frequency measures available for the German language, we find that the commonly used Celex frequencies are the least powerful to predict lexical decision times. Better results are obtained with the Leipzig frequencies, the dlexDB frequencies, and the Google Books 2000-2009 frequencies. However, as in other languages the best performance is observed with subtitle-based word frequencies. The SUBTLEX-DE word frequencies collected for the present ms are made available in easy-to-use files and are free for educational purposes.

Using a novel technique providing simultaneous resolution with respect to the wave vector and frequency of magnons, we observed the formation of a Bose-Einstein condensate documented by the narrowing of the magnon distribution in phase space. Based on the measured width of the distribution we determined the effective correlation length of the condensate, which appears to be anisotropic, reflecting the anisotropy of the magnon dispersion spectrum.

We study interlayer exchange coupling in epitaxial Fe/Fe(0.56)Si(0.44)/Fe trilayers. Iron-silicide spacers with high structural and compositional homogeneity for thicknesses up to 34 A are grown by coevaporation from two electron-beam sources. The coupling strength oscillates with spacer thickness for temperatures from 20 to 300 K with two antiferromagnetic maxima at 12 and 26 A, and it clearly increases with decreasing temperature down to 80 K. We conclude that the coupling across ordered Fe(1-x)Si(x) ( x approximately 0.5) is described by the conventional theory of interlayer coupling across metallic spacers.

We present a simple approach based on continuum theory to calculate spin-wave frequencies in thin magnetic multilayers taking into account both the nonuniform static and dynamic magnetizations, which are present in systems with strong interlayer exchange coupling. The calculation includes in-plane static magnetization, the canted and twisted state, bilinear and biquadratic interlayer exchange coupling, and the dynamic dipolar coupling. Therefore, we are able to compute accurate spin-wave frequencies in strongly antiferromagnetic coupled trilayers over a full hysteresis loop. We consider the field dependence of the spin-wave frequencies of an epitaxial Fe͑001͒/Si-wedge/Fe sample with strong antiferromagnetic coupling measured by Brillouin light scattering and find excellent agreement with the model calculation. The fits of the experimental curves verify the existence of the twisted state and allow determining the coupling constants with high precision.

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Magneto-optical ͑MO͒ Kerr effect ͑MOKE͒ magnetometry is one of the most widely employed techniques for the characterization of ferromagnetic thin-film samples. Some information, such as the magnitude of coercive fields or anisotropy strengths, can be readily obtained without any knowledge of the optical and MO properties of the material. On the other hand, a quantitative analysis, which requires precise knowledge of the material's index of refraction n and the MO-coupling constants K and G, is often desirable, for instance, for the comparison of samples which are different with respect to ferromagnetic layer thicknesses, substrates, or capping layers. While the values of the parameters n and the linear MO-coupling parameter K reported by different authors usually vary considerably, the relevant quadratic MO-coupling parameters G even for Fe are completely unknown. Here, we report on measurements of the thickness dependence ͑0-60 nm͒ of the linear and quadratic magneto-optical effects in epitaxial bcc-Fe͑001͒ wedge-type samples performed at a commonly used laser wavelength of 670 nm. By fitting the thickness dependence we are able to extract a complete set of parameters n, K, ͑G 11 − G 12 ͒, and G 44 for the quantitative description of the MOKE response of bcc-Fe͑001͒. We find the parameters n, K, and G to significantly differ for films thinner than about 10 nm as compared to those for thicker films, which is indicative of a thickness dependence of the electronic properties or of surface contributions to the MOKE. The magnitude of the quadratic magneto-optical effect is found to be about one-third of the record values reported recently for Co 2 FeSi.

We have studied experimentally with high spatial resolution the nonlinear eigenmodes of microscopic Permalloy elliptical elements. We show that the nonlinearity affects the frequencies of the edge and the center modes in an essentially different way. This leads to repulsion of corresponding resonances and to nonlinear mode hybridization resulting in qualitative modifications of the spatial characteristics of the modes. We find that the nonlinear counterparts of the edge and the center modes simultaneously exhibit features specific for both their linear analogues.

The authors report on current-induced magnetization switching ͑CIMS͒ in single-crystalline nanopillars. Fe͑14 nm͒ /Cr͑0.9 nm͒ /Fe͑10 nm͒ /Ag͑6 nm͒ /Fe͑2 nm͒ multilayers are deposited by molecular-beam epitaxy. The central Fe layer is coupled to the thick one by interlayer exchange coupling over Cr, while the topmost Fe layer is decoupled. Nanopillars with 150 nm diameter are prepared by optical and e-beam lithographies. The opposite spin scattering asymmetries of the Fe/ Cr and Fe/ Ag interfaces enabled the authors to observe normal and inverse CIMS for the two subsystems, which are combined in a single device. At high magnetic fields, steplike resistance changes are measured at positive currents and are attributed to current-driven magnetic excitations.