Hall Effect in Evaporated Films of Iron, Cobalt, Nickel, Palladium, and Platinum

Abstract

Hall coefficients of evaporated films.—The Hall coefficients for films of Fe, Co, Ni, Pd, and Pt, 6 to 270μμ thick, deposited on surfaces at a distance less than the mean free path from the evaporating filament, were measured. For films of the ferromagnetic metals, Fe, Co, Ni, the Hall coefficients were respectively 1.4, 4.9, and 7.8 times the values for the corresponding metals in bulk, these factors being in the order of the atomic numbers of the elements. For the paramagnetic, negative Hall effect metals, Pd and Pt, the Hall coefficients were 0.66 and 0.64 times the values for the metals in bulk. The increased Hall effect for the films of the ferromagnetic metals seems closely related to ferromagnetism, although Ni, the least ferromagnetic of the three, shows the greatest variation. Films of Ir and Rh, formed at a distance less than the mean free path from the evaporating filament, showed for Ir a positive Hall effect as in bulk, and for Rh no detectable effect.