Thin films of [Fe(H(2)Bpz)(2)(phen)] (1) and [Fe(H(2)Bpz)(2)(bipy)] (2) are prepared by vacuum deposition and investigated with respect to their spin crossover behaviour. For the first time light-induced excited spin state trapping (LIESST) is observed in such systems. T(1/2) and T(LIESST) in the films are in agreement with the bulk values.

Magnetic tunnel junctions consisting of a magnetically stable reference layer plus a magnetostrictive sense layer separated by an insulating MgO tunnel barrier have been fabricated and characterized particularly with regard to their application as strain and pressure sensors. Using a four-point-bending apparatus it has been proven that the application of mechanical stress causes the magnetization of the sense layer to rotate, while simultaneously the resistance of the strained magnetic tunnel junction changes. So far gauge factors up to 840 have been reached in resistance versus strain measurements. It has been demonstrated that these magnetic tunnel junctions also work as highly sensitive pressure gauges when placed on bulk or surface micromachined membranes.

The thickness dependent generation of magnetic stripe domains in NiFe films is investigated by in-depth magnetic domain and micromagnetic analysis, as well as complementary analysis of the microstructure by x-ray diffraction and transmission electron microscopy. A gradient of perpendicular magnetic anisotropy with film thickness is found. Micromagnetic simulations show that the anisotropy gradient results in an asymmetric stripe domain configuration. Columnar grain coarsening and texture development with thickness are derived from the microstructural investigations. The variations correspondingly lead to the gradient of magnetic anisotropy and to an asymmetric magnetic stripe domain structure.

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A magneto-optical imaging approach for the simultaneous imaging of multiple magnetization components is demonstrated. The method is applied to investigate complex magnetization reversal processes in single crystal iron and patterned amorphous magnetostrictive ferromagnetic structures. The use of a splitted optical illumination and observation path allows for the direct extraction of different complementary magnetic information. Real-time in-plane vector magnetization imaging reveals complicated domain arrangement processes in magnetostrictive films due to locally varying stress induced magnetic anisotropy. Magnetic domain features concealed by standard domain imaging techniques are directly exposed.