Crossover from anomalous to conventional antiferromagnetism in Pd-doped UPt3 studied via cantilever magnetometry

UPt 3 exhibits an anomalous form of antiferromagnetic (AF) order, which is thought to be fluctuating in time. Substitution of Pd for Pt induces conventional AF behavior. In an attempt to further probe the possible existence of an AF quantum critical point in U(Pt 1-x Pd x ) 3 at x c ∼0.006, we have made cantilever magnetometer measurements on single crystalline U(Pt 1-x Pd x ) 3 for x = 0.01, 0.02, and 0.05 in magnetic fields of 6 T. While readily observable for the samples with x = 0.02 and 0.05, we find no evidence for the AF transition at x = 0.01, in contrast to μSR measurements.