Hyperfine field distribution at 59Co in amorphous Fe(Co)79P13B8 alloys

Abstract

We report the results of 59Co spin-echo measurements at 4.2 °K in amorphous alloys of composition (Fe100−xCox)79P13B8, with x=1, 3, 4, 10, 20, 30, 40, 60, 70, 80, 90 and 100. A comparison is made also with the 59Co NMR spectrum in a-Co3B. Evidence is shown for large quadrupolar effects in the dilute alloys. The influence of short-range order on the hyperfine field distribution in concentrated Co alloys is pointed out.