Intrinsic magnetic behavior of single and multilayered metal-evaporated films

Metal-evaporated CoNi tapes constituted of one layer and of three layers ar e studied. In these obliquely deposited films, the angle of the inclined co lumns on the tape plane conditions the magnetic properties of the medium. T he increase of the angle enhances the magnetization, but decreases the coer civity. Multilayered thin films have large magnetization and contemporarily high coercivity. The magnetostatic interactions are positive, or magnetizi ng, in the triple-layered tape and negative, or demagnetizing, in the singl e-layered tape. This explains the larger magnetization and remanence of the multilayered tape. The stronger shape anisotropy, due to the larger magnet ization, makes smaller the angle of the easy axis on the plane in triple-la yered tape, notwithstanding the larger inclination of the columns. The anal ysis of the magnetization reversal mode indicates that in the triple-layere d tape the reversal mechanism is partly coherent rotation, while in the sin gle layered it is more probably incoherent. Such evolution of the basic pro cess of magnetization explains the large coercivity of the multilayered tap e. (C) 2000 American Institute of Physics. [S0021-8979(00)46308-5].