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Photoemission electron microscopy (PEEM) is widely used for the study of magnetic surfaces and thin films. Ferromagnetic and antiferromagnetic microstructures are investigated exploiting magnetic circular and linear dichroism in the soft X-ray range using tuneable synchrotron radiation. Local dichroism spectroscopy gives access to magnetic moments of the elements in compounds or multilayer materials. Beyond these achievements, the method bears a high future potential with respect to an increased lateral resolution via aberration correction of the electron optics and a high time resolution in the 100 ps range for the study of dynamic processes. In addition, photoelectron spin polarisation analysis implemented into PEEM provides a novel local probe for the investigation of spin dynamics. The current instrumental state-of-the-art and the future potential of PEEM in the field of surface and thin-film magnetism are discussed and illustrated by recent examples. [Copyright &y& Elsevier]

The interaction of intense, pulsed laser radiation with surfaces results in non-linear optical effects that are responsible for emission of electrons even if the photon energies are below the work function. In the present study, photoelectrons have been excited by means of femtosecond laser pulses from a frequency doubled Ti:sapphire laser with a photon energy of 3.1 eV. The spatial distribution of the photo emitted electrons was imaged using a photoemission electron microscope. All samples exhibit centres of enhanced second or higher order photoemission yield, so called ‘hot spots’. These ‘hot spots’ were preferentially excited with s-polarised light. This behaviour may be explained on the basis of a microscopic model assuming localised plasmon excitations in small particles. Lead films and pentacene layers adsorbed on silicon have been studied. The photoelectron yield depends strongly on the sample topography and the polarisation of the photons. The polarisation and power dependence of the multi-photon photoemission yield were studied. Clear evidence for three-photon contributions has been found although two-photon photoemission is sufficient to overcome the surface barrier. [Copyright &y& Elsevier]