Ferromagnetic resonance of Ni(111) on Re(001)

The magnetic anisotropy and the magnetic relaxation between 1 and 10 GHz of ultrathin Ni(1 1 1) films on Re(0 0 0 1) is studied by ferromagnetic reson ance in ultrahigh vacuum. For 6-14 monolayers a small-bulk-like anisotropy is measured indicating the nearly complete structural relaxation of Ni into its cubic FCC structure. Around 12 ML a change of sign in the anisotropy r eflects the change in surface morphology known from previous STM results. T he ferromagnetic resonance linewidth shows a characteristic maximum near th e ferro- to paramagnetic phase transition which is caused by the increase o f magnetic fluctuations and an enhanced relaxation of the magnetization. (C ) 2000 Elsevier Science B.V. All rights reserved.