Magnetic properties of TbPtGe2 in high magnetic field

Magnetization of a TbPtGe2 polycrystalline sample has been measured at a high magnetic field up to 22.5 T. The magnetization curves show a two-step metamagnetic process for the low temperature phase (below 12.5 K) and have paramagnetic character for the high temperature phase. For the low temperature phase the values of both critical fields H C1 and H C2 change slightly with increasing temperature. In the high temperature phase the critical field H C1 quickly decreases with increasing temperature. In addition, specific heat studies were performed up to magnetic fields of 9 T to confirm the magnetic phase diagram.