Effect of oxygen surfactant on the magnetic and structural properties of Co films grown on Cu(110) - art. no. 024408

It was found that atomically flat Co(110) films could be grown on Cu(110) u sing O as a surfactant. To obtain detailed knowledge on the effect of O on the growth, as well as on the magnetic properties of Co overlayer, we carri ed out an investigation on this system using Auger electron spectroscopy, l ow-energy electron diffraction, surface magneto-optic Kerr effect (SMOKE), and scanning tunneling microscopy. With O as a surfactant, the initial grow th Of CO (<1 ML) results in a flat monolayer structure. When the Co is thic ker than 1 ML, three-dimensional clusters begin to form. These clusters bec ome ordered islands at 3 ML Co and coalesce at <similar to>5 ML Co. Above 5 ML Co, layer-by-layer growth resumes. No significant Cu segregation is obs erved. SMOKE studies at room temperature show that the Co film is magnetic above similar to5 ML,Co, with the magnetization easy axis along the [001] d irection. On the other hand, without using oxygen as a surfactant, Co grows three-dimensionally on Cu(110). The Co overlayer has its easy magnetizatio n axis along the [001] direction, but the onset of the magnetization was ob served at 11 hit Co at room temperature.