Thermal and electronic transport in CeRu2Al10: Evidence for a metal–insulator transition

A first report of physical properties of the ternary intermetallic compound CeRu2Al10 is given. The electrical resistivity below room temperature shows activated behaviour with a narrow gap of Δ≃20K before the onset of a sharp peak in ρ(T) below T*=27K. The Hall coefficient as well as the thermoelectric power are overall positive, and both increase in a similarly sharp manner below T*. The lattice part of the thermal conductivity indicates phonon coupling of the heat transport at T*, possibly underlying a lattice transformation that accompanies the putative metal-to-insulator and magnetic phase transitions.