Coordination-number dependence of magnetic hyperfine fields at (111)Cd on Ni surfaces

Phys Rev Lett. 2002 Jun 17;88(24):247201. doi: 10.1103/PhysRevLett.88.247201. Epub 2002 May 31.

Abstract

Ferromagnetic Ni surfaces were investigated on an atomic scale using the perturbed angular correlation spectroscopy probe (111)Cd. A comprehensive set of data for magnetic hyperfine fields (B(hf)) at various probe sites is presented. A field variation from -7 T in Ni bulk to the surprisingly large value of 16 T at the adatom position on Ni(111) is observed. A continuous nonlinear dependence is found, correlating the experimental B(hf) values with the number of their nearest Ni neighbors. The data are discussed on the basis of recent calculations on B(hf) values at sp-element impurities on ferromagnetic surfaces.