The reflection properties of 300 nm periodically structured silicon surfaces with depth varying between 35 and 190 nm, prepared by interference lithography, were examined in the range 200 nm<λ<3000 nm. A decrease in the reflectivity that becomes stronger with increasing structure depth is observed below 1000 nm. This broad-band reduction is caused by diffraction effects at short wavelengths and by the `moth-eye effect' at long wavelengths. The results show a universal behaviour in the optical-path to wavelength ratio dependence of the reflectivity and are in good agreement with the results obtained for the `moth-eye effect' from the effective medium theory.

We present experimental results on the characterization of commercially available magnetic force microscopy (MFM) thin film tips as a function of an external magnetic field. Well defined magnetic stray fields are produced using current carrying rings with radii ranging between 603 and 2369 nm fabricated by electron-beam lithography directly imaged by MFM. Treating the MFM tip as a point probe, the analysis of the image contrast as a function of both the magnetic stray field and the lift height allows for a quantitative determination of effective magnetic dipole and monopole moments of the tip as well as their imaginary location within the real physical tip. Our systematic study gives a quantitative relationship on how absolute values of the magnetic dipole and monopole moments and their location within the tip depend on a characteristic decay length of the z component of the magnetic field being detected. From this we can estimate the effective tip volume of the real physical thin film tip relevant in MFM imaging.

We describe a modification of conventional dynamic light scattering (DLS) using a CCD camera as optical area detector. Scattered intensity autocorrelation functions are determined using both ensemble- and time-averaging. Therefore, the new setup allows for much shorter measurement times compared to conventional DLS. Our apparatus has been checked by investigating a dilute dispersion of polystyrene (PS)–microgel lattices in glycerol. The results agree well with DLS measurements using the standard setup. Further, we present data for ultraslow dynamical processes in highly concentrated nonergodic suspensions of PS–microgel lattices, where the new technique, due to its shorter measurement time and much better statistical accuracy as compared to conventional DLS, is most useful.

We report on the synthesis of nearly monodisperse phase-separated polymer latexes with a well-defined core−shell morphology. Styrene/diisopropenylbenzene and tert-butyl acrylate/ethylene glylcol-diacrylate were used for either the core or shell of the composite microgel particles. A major concern of the paper is the detailed characterization of the core−shell and inverse core−shell particles by static and dynamic light scattering, transmission electron microscopy, solid-state NMR, and the analytical ultracentrifuge. The effect of the cross-linking agent on the final phase-separated morphology is discussed and compared with theoretical predictions.

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