Observation of field-induced single impurity behavior in the heavy fermion compound [formula omitted

Abstract

We have performed heat capacity measurements in magnetic fields to 90 kOe on single crystals of the cubic heavy fermion compound Ce 3 Co 4 Sn 13 . In zero field, there are no signs of long-range magnetic order down to 0.35 K. However, C / T increases rapidly below 2 K, reaching a very large maximum value of ∼ 4 J / mol Ce–K around 0.8 K in zero field, and the high-field magnetic entropy approaches R ln 2 at 20 K. Above 25 kOe, the data are consistent with a Kondo impurity with T K = 1.2 K . Short-range magnetic correlations are suppressed by magnetic fields giving way to single impurity behavior above 25 kOe.