Magnetic Phase Diagram of the new Heavy Fermion Compound Ce2PtIn8

We report on the discovery and investigation of a new 218 heavy fermion compound. Crystals have been synthesized from In-flux. Structurally, Ce2PtIn8 is located between the cubic CeIn3 and the more two-dimensional CeTIn5 (T = transition metal) type of compounds. The weak anisotropy of the paramagnetic susceptibility suggests rather 3D magnetic correlations. Specific heat, electrical resistivity and magnetization measurements revealed that Ce2PtIn8 orders antiferromagnetically below Tn = 2.1 K. An order-to-order transition is observed at Tm = 2 K. Similarities in the H - T phase diagram to other CenTmIn3n+2m (T = Rh, Pt) compounds point to a pressure-induced quantum phase transition (QPT) which, according to the tentative location of Ce2PtIn8 in the recent proposed global phase diagram for QPT, would be of spin density wave type.