A comparison of the systematics of the spin-glass susceptibility peaks in P d Mn with an effective-field model

We present new measurements of the ac susceptibility of two PdMn alloys containing 5.0 and 5.5 at. % Mn in approximately 50 static biasing fields up to 1 kOe, as well as a survey of previous data on more concentrated samples, in an attempt to establish the details of the field suppression of the spin-glass peaks in this system. These results are compared with the predictions of an arbitrary spin effective-field model. Both the experimental data and the theoretical predictions indicate that the rate of this suppression increases dramatically as one approaches the ferromagnetic–spin-glass critical point (i.e., as η=J̄0/J̄→1, where J̄0 and J̄ refer to the center and width of the exchange distribution).