Holger Weinforth :

Strukturelle, elektrische und magnetische Eigenschaften dünner granularer CoxC1-x und (Co/Pt)xC1-x-Schichten

Dissertation angenommen durch: Universität Duisburg-Essen, Campus Duisburg, Fakultät für Naturwissenschaften, Institut für Physik, 2003-03-17

BetreuerIn: Prof. em. Dr. Eberhard F. Wassermann , Universität Duisburg-Essen, Campus Duisburg, Fakultät für Naturwissenschaften, Institut für Physik

GutachterIn: Prof. em. Dr. Eberhard F. Wassermann , Universität Duisburg-Essen, Campus Duisburg, Fakultät für Naturwissenschaften, Institut für Physik
GutachterIn: Prof. Dr. Wolfgang Kleemann , Universität Duisburg-Essen, Campus Duisburg, Fakultät für Naturwissenschaften, Institut für Physik

Schlüsselwörter in Englisch: TEM, SQUID, granular magnetic films, magnetization reversal, Stoner Wohlfarth particle, magnetorsistance, magnetic coupling, exchange interaction, magnetic dipolar interaction

  
   
 Klassifikation     
    Sachgruppe der DNB: 530 Physik
  
   
 Abstrakt     
   

Abstrakt in Englisch

Granular CoxC1-x and (Co/Pt)xC1-x thin films with different metal-volume fractions x are prepared by simultanious electron beam evaporation of Co or CoPt and C targets. The films are condensed on NaCl- and quartz substrates. The structure of the films is influenced by choosing different substrate temperatures Ts in the range between 20°C and 350°C as well as by annealing the thin film samples after generation at temperatures Ta between 200°C and 700°C. The structural properties of the films are examined by means of transmission electron microscopy and electron diffraction. Electrical resistivity of the films is measured in the temperature range between T = 4.2K and T = 300K. In order to reveal the magnetic properties of the granular thin films a SQUID magnetometer is used. In addition to the measurement of hysteresis loops at T = 4.2K and T = 300K, remanent magnetisation curves are measured in order to examine the magnetic coupling between the particles of the granular films. Additionally magnetoresistance measurements are performed at T = 4.2K. Strukturelle, elektrische und magnetische Eigenschaften dünner granularer CoxC1-x und (Co/Pt)xC1-x-Schichten Structural, electric and magnetic properties of thin granular CoxC1-x and (Co/Pt)xC1-x films