Heusler compounds are promising candidates for future spintronics device applications. The electronic and magnetic properties of Co 2 Cr 0.6 Fe 0.4 Al, an electron-doped derivative of Co 2 CrAl, are investigated using circularly polarized synchrotron radiation and photoemission electron microscopy (PEEM). Element specific imaging reveals needle shaped Cr rich phases in a homogeneous bulk of the Heusler compound. The ferromagnetic domain structure is investigated on an element-resolved basis using x-ray magnetic circular dichroism (XMCD) contrast in PEEM. The structure is characterized by micrometre-size domains with a superimposed fine ripple structure; the lateral resolution in these images is about 100 nm. The domains look identical for Co and Fe giving evidence of a ferromagnetic coupling of these elements. No ferromagnetic contrast is observed at the Cr line. Magnetic spectroscopy exploiting XMCD reveals that the lack of magnetic moment, detected in a SQUID magnetometer, is mainly due to the moment of the Cr atom.

We use photoemission electron microscopy to measure the dielectric response of nanostructured CoPt multilayers. The polarization dependence of the spatially resolved two-photon photoemission yield can be directly related to optical laser fields near the edges of the nanodots. Photoelectron spin analysis reveals that enhanced optical near fields can be used to induce a local demagnetization of the sample within 400 fs following fs laser excitation. Experiments on ultrathin Co films demonstrate that for high fluences the observed demagnetization timescale of 130 fs is masked by a novel spin dependent bleaching effect in two-photon photoemission.

We report on a picosecond time-resolved x-ray magnetic circular dichroic-photoelectron emission microscopy study of the evolution of the magnetization components of a microstructured permalloy platelet comprising three cross-tie domain walls. A laser-excited photoswitch has been used to apply a triangular 80 Oe, 160 ps magnetic pulse. Micromagnetic calculations agree well with the experimental results, both in time and frequency, illustrating the large angle precession in the magnetic domains with magnetization perpendicular to the applied pulse, and showing how the magnetic vortices revert their core magnetization while the antivortices remain unaffected.

The authors have successfully employed the charged particle nanopatterning (CHARPAN) technology for nanostructuring of a metal mold insert for a conventional injection molding machine. High-precision diamond-milled Ni–Cu mold inserts have been nanopatterned with 10 keV argon ion multibeam milling with feature sizes as small as 50 nm. A variety of structures such as circles, hexagons, and lines in different dimensions, with positive and negative shapes, have been fabricated in the metal mold. These structures have been successfully replicated in polymethylpentene samples by injection molding. To the authors’ best knowledge, the CHARPAN technology is one of the very few technologies that allow for resistless nanostructuring a field size of 25×25 μm2 into a metal mold in a single shot. This is of high importance for the practical injection molding fabrication of nanostructured polymer devices such as optical biosensors.

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