The spin-glass state of Y1-xUxPd3

We have performed a detailed study of the magnetization of Y0.6U0.4Pd3 (T-f similar to 10 K), which shows thermal, transport, and magnetic properties typical of a spin-glass system. Strong irreversibility is observed among our zero-field-cooled and field-cooled measurements in fields as large as 30 kOe. Thus, the freezing temperature displays an unusual weak dependence with field. We observe a very slow temporal dependence of the magnetization below the freezing temperature. The nonlinear susceptibility coefficients extracted from our data show an increase by a factor of approximately 20 when approaching the freezing temperature from above, but do not show a true divergence at T-f, and a scaling analysis does not seem to be possible. We compare these results with those expected for classical spin glasses, and propose a possible mechanism for the onset of frustration below x=0.45 in Y1-xUxPd3. (C) 1996 American Institute of Physics.