MAGNETIC PHASE-TRANSITION IN A 2-DIMENSIONAL SYSTEM - P(1X1)-NI ON CU(111)

The magnetic phase transition of ultrathin epitaxial Ni films on Cu(111) is studied using the magneto-optic Kerr effect. Analysis of the thickness and temperature dependence of the spontaneous magnetization yields a shift exponent =1.440.2, in good agreement with previous experimental studies of thin Ni layers, and a critical exponent =0.240.07 in good agreement with a recent study of p(1×1)-Fe on Au(100). In-plane symmetry does not appear to play an important role in critical behavior of these systems. © 1990 The American Physical Society.