New As-based filled skutterudite compounds GdFe4As12 and TbFe4As12 have been
synthesized under high pressure. The samples have a cubic structure with lattice parameters
a=8.3024 ˚A, and 8.2961 ˚A, respectively. Both compounds show metallic behavior and a
pronounced kink at low temperature in the temperature dependence of resistivity. Magnetic
measurements revel that GdFe4As12 and TbFe4As12 exhibit a ferromagnetic-like phase transition
at 56K and 38K, respectively. The unexpectedly high transition temperatures could be related
to the interaction of Gd (or Tb) 4f moments with Fe 3d moments.