抄録
Films of MnBiAl composition, prepared by interleaving Mn and Bi layers by vacuum evaporation into a multilayer with an AI-layer at half-thickness, were studied. For Mn contents of 40 to 70 at% and AI dopings below 15 at%, the films, when annealed at temperatures between 230 and 420°C, became ferromagnetic with magnetization perpendicular to the film plane. Adding AI caused the film crystallite size to decrease to about 50 nm, and to depress the phase transitions between the low (lhp)- and high (htp)- temperature phases. Compared with MnBi films, no significant changes in crystal structure, lattice constants and Curie temperature were observed. The Kerr rotation spectrum shows a maximum value of 1.78° at about 700 nm and a peak of 1.5° at 370 nm. The reflectivities vary from 40 to 60% with wavelength change from 330 to 800 nm.
