Magnetoresistance and magnetic properties of Co/Ir multilayers on MgO(110) substrates H. Yanagihara Institute of Applied Physics, University of Tsukuba, Tsukuba 305, Japan K. Pettit IBM Almaden Research Center, San Jose, California 95120-6099 M. B. Salamon Department of Physics, University of Illinois, Urbana, Illinois 61801 Eiji Kita Institute of Applied Physics, University of Tsukuba, Tsukuba 305, Japan S. S. P. Parkin IBM Almaden Research Center, San Jose, California 95120-6099 A Co(12 Å)/Ir(16 Å) multilayer deposited on MgO(110) is found to have a strong uniaxial anisotropy, comparable to bulk hcp-Co. Experimental results suggests the crystallographic relation of (100)[001]Co/(110)[001]Ir/(110)[001]MgO. A remarkable difference is seen between easy and hard axis magnetization processes, due to competition between the in-plane anisotropy and the exchange coupling. Considering the characteristics of the MH loops and magnetoresistance curves, we simulate the magnetization and magnetoresistance processes numerically. The results of our simulation indicate the existence of biquadratic coupling in Co/Ir(110). ©1997 American Institute of Physics.