Growth and magnetic ordering of Ni and Co films on Rh(001) investigated with second-harmonic generation

Second-harmonic generation (SHG) was used to study the magnetic properties of cobalt and nickel films on Rh(0 0 1) during growth. We observed strong s tress-induced magnetostrictive effects due to the large lattice mismatch of 7.3% for Co and 7.9% for Ni. For Co films in-plane magnetic ordering start s at 2 ML at room temperature and remains in-plane up to about 23 ML. A shi ft of the relative phase between magnetic and nonmagnetic SH contributions leads to sign changes of the magnetic contrast for both, p --> P and s --> P polarization combinations. In case of Ni, no in-plane magnetization was o bserved at room temperature but we could verify the onset of perpendicular magnetization between 5 and 6ML. (C) 2001 Elsevier Science B.V. All rights reserved.