Anomalous metamagnetic behavior of TbCu2Ge2 single crystal

The magnetic characteristics of the single crystal compound TbCu2Ge2 have been studied by magnetic susceptibility and magnetization measurements. The susceptibility shows two anomalies at T-N = 12.3 K and T-t = 9.3 K. The magnetic easy direction is the [I 10] direction in the basal plane. The magnetization along the easy direction in the basal plane shows a multi-step (at least four steps) metamagnetic process. No significant change of the process is observed at T, A one-step metamagnetic transition appears around 17 T in the hard c-axis magnetization process. This transition persists above TN up to 25 K where the susceptibility shows a broad peak. The origin is unsolved yet. (C) 2004 Elsevier B.V. All rights reserved.