Measurement of Magnetic Field Distributions

Abstract

In many circumstances the Mössbauer effect competes with NMR and other methods in the measurement of magnetization through its effect on hyperfine fields. In the case where the hyperfine field is unique, as in iron [1], or where only a few well-defined values of the hyperfine field appear, the Mössbauer method may be inferior to NMR, which is capable of much higher precision. In situations where there is a large spread in hyperfine fields, the Mössbauer method provides a unique tool in the determination of this spread. An example of such a case is the hyperfine field distribution at iron nuclei in the ferromagnetic Fe-Pd alloys in the vicinity of the transition temperature. The properties of the Fe-Pd system have been reported elsewhere [2, 31. The particular alloy on which we report is Fe 13.2-Pd 86.8 in which the iron atoms are assumed to be randomly distributed in the face-centered cubic palladium structure. The important features of the Mössbauer spectra are illustrated in Figs. 1 and 2.