Optical detection of spin transport in non-magnetic metals

We determine the dynamic magnetization induced in non-magnetic metal wedges composed of silver, copper and platinum by means of Brillouin light scattering (BLS) microscopy. The magnetization is transferred from a ferromagnetic Ni80Fe20 layer to the metal wedge via the spin pumping effect. The spin pumping efficiency can be controlled by adding an insulating but transparent interlayer between the magnetic and non-magnetic layer. By comparing the experimental results to a dynamical macroscopic spin-transport model we determine the transverse relaxation time of the pumped spin current which is much smaller than the longitudinal relaxation time

Pressure control of nonferroelastic ferroelectric domains in ErMnO3

Mechanical pressure controls the structural, electric, and magnetic order in solid-state systems, allowing tailoring of their physical properties. A well-established example is ferroelastic ferroelectrics, where the coupling between pressure and the primary symmetry-breaking order parameter enables hysteretic switching of the strain state and ferroelectric domain engineering. Here, we study the pressure-driven response in a nonferroelastic ferroelectric, ErMnO3, where the classical stress–strain coupling is absent and the domain formation is governed by creation–annihilation processes of topological defects. By annealing ErMnO3 polycrystals under variable pressures in the MPa regime, we transform nonferroelastic vortex-like domains into stripe-like domains. The width of the stripe-like domains is determined by the applied pressure as we confirm by three-dimensional phase field simulations, showing that pressure leads to oriented layer-like periodic domains. Our work demonstrates the possibility to utilize mechanical pressure for domain engineering in nonferroelastic ferroelectrics, providing a lever to control their dielectric and piezoelectric responses

Verfahren und Vorrichtung zum Einstellen eines Arbeitspunktes beim reaktiven Sputtern

DE 102006049608 A1 UPAB: 20080724 NOVELTY - Device for adjusting a working point during reactive sputtering within a defined sputtering region comprises a measuring unit (15) for acquiring the intensity values from a spectral line of the emission of a target material and the intensity values from a spectral line of the emission of an inert gas, an evaluating unit (16) for calculating the intensity ratios and a control circuit for controlling the reactive gas flow into a vacuum chamber so that the actual intensity ratio value corresponds to the theoretical value calculated using the evaluating unit. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a method for adjusting a working point during reactive sputtering within a defined sputtering region using the above device. USE - Device for adjusting a working point during reactive sputtering within a defined sputtering region. ADVANTAGE - The working point can be easily adjusted

Motivation und Persönlichkeit: Von der Analyse von Teilsystemen zur Analyse ihrer Interaktion

Brunstein JC, Maier GW, Schultheiß OC. Motivation und Persönlichkeit: Von der Analyse von Teilsystemen zur Analyse ihrer Interaktion. In: Jerusalem M, Pekrun R, eds. Emotion, Motivation und Leistung. Göttingen: Hogrefe; 1999: 147-167

Electrical insulation properties of sputter-deposited SiO2, Si3N4 and Al2O3 films at room temperature and 400 degrees C

In this paper the breakdown field strength and resistivity of sputter-deposited Al2O3, SiO2 and Si3N4 layers are investigated in the temperature range between room temperature and 400 degrees C. All the investigated layers showed excellent insulation properties, even at elevated sample temperature. One example of industrial application is the deposition of electrical insulation layers onto the membranes of pressure sensors using cluster type sputter equipment

Cytotoxicity, chemical stability, and surface properties of ferroelectric ceramics for biomaterials

Surface chemistry and topo-physical properties determine the interactions of biomaterials with their physiological environment. Ferroelectrics hold great promise as the next generation of scaffolds for tissue repair since they feature tunable surface electrical charges, piezoelectricity, and sensing capabilities. We investigate the topography, wettability, chemical stability, and cytotoxicity in salient ferroelectric systems such as (1-x) (Na1/2Bi1/2)TiO3–xBaTiO3, (1-x)Ba(Zr0.2Ti0.8)O3-x(Ba0.7Ca0.3)TiO3, and Pb(Zr,Ti)O3 to test their suitability as biomaterials. The lead-free ferroelectrics promote in vitro cell viability and proliferation to a considerably high extent. 0.94 mol % (Na1/2Bi1/2)TiO3–0.06 mol% BaTiO3 showed the greatest potential leading to a cell viability of (149 +- 30)% and DNA synthesis of (299 +- 85)% in comparison to the reference. Lead leaching from Pb (Zr,Ti)O3 negatively affected the cultured cells. Wettability and chemical stability are key factors that determine the cytotoxicity of ferroelectrics. These variables have to be considered in the design of novel electroactive scaffolds based on ferroelectric ceramics

Pressure Control of Nonferroelastic Ferroelectric Domains in ErMnO₃

Mechanical pressure controls the structural, electric, and magnetic order in solid-state systems, allowing tailoring of their physical properties. A well-established example is ferroelastic ferroelectrics, where the coupling between pressure and the primary symmetry-breaking order parameter enables hysteretic switching of the strain state and ferroelectric domain engineering. Here, we study the pressure-driven response in a nonferroelastic ferroelectric, ErMnO3, where the classical stress–strain coupling is absent and the domain formation is governed by creation–annihilation processes of topological defects. By annealing ErMnO3 polycrystals under variable pressures in the MPa regime, we transform nonferroelastic vortex-like domains into stripe-like domains. The width of the stripe-like domains is determined by the applied pressure as we confirm by three-dimensional phase field simulations, showing that pressure leads to oriented layer-like periodic domains. Our work demonstrates the possibility to utilize mechanical pressure for domain engineering in nonferroelastic ferroelectrics, providing a lever to control their dielectric and piezoelectric responses