Interface alloying at Fe/Cr interfaces and its role in exchange coupling, angular resolved Auger electron, magneto-optic Kerr effect, and Brillouin light scattering studies

Angular resolved Auger electron studies were carried out for Fe whisker/Cr(001) interfaces which were prepared at 100, 180, 246, and 296 degrees C. The Cr atoms penetrate progressively into the second (counting from the surface) atomic layer at 100, 180, and 246 degrees C. At 296 degrees C the Cr atoms enter the third atomic layer. No noticeable fraction of the Cr atoms was found in the fourth atomic layer. The exchange coupling was studied in Fe whisker/Cr/Fe(001) films which were grown in a nearly perfect layer by layer mode. Magneto-optic Kerr effect and Brillouin light scattering measurements showed that the measured change in the phase of the short wavelength oscillations, the presence of a slowly varying exchange coupling bias, and the small measured values of exchange coupling are caused by the same mechanism: interface alloying. The exchange coupling in Fe whisker/Cr/nFe specimens, for n=10, 20, 30, and 40 ML, showed no obvious dependence on the Fe layer thickness. (C) 1996 American Institute of Physics.