Exchange coupling through spin density wave Cr(001) using Fe whisker substrates

Exchange coupling through spin density wave in Fe whisker/Cr/Fe(001) struct ures was studied by Brillouin light scattering (BLS) and longitudinal magne to-optical Kerr effect (MOKE) techniques. It will be shown that interface a lloying at the Fe whisker/Cr interface profoundly affects the behavior of s hort wavelength oscillations. The first crossover to antiferromagnetic coup ling occurs at 5 monolayers (ML), the phase of short-wavelength oscillation s is reversed compared to that expected for the spin density wave in Cr(001 ), and the strength of coupling is significantly decreased from that obtain ed from first principle calculations. Using Cu and Ag atomic layers between the Cr(001) and Fe(001) films, heterogeneous interfaces showed that the ex change coupling in Cr(001) is strongly affected by electron multiple scatte ring. It appears that electron quantum well states in the Fe film play no i mportant role in the strength of the exchange coupling when the Fe film is bounded on one side by Au, but they become important when the Fe film is bo unded by Cr on both sides. (C) 2000 American Institute of Physics. [S0021-8 979(00)31108-2].