Synthesis of LaRhAsO and superconductivity within the LaFe1−xRhxAsO system

The compound LaRhAsO is reported for the first time. We show that an entire LaFe1−xRhxAsO solid solution is possible. Powder X-ray diffraction, resistivity and magnetic measurements were carried out on polycrystalline samples. Superconductivity onset is observed for x = 0.05, 0.10, and 0.15 with a maximum resistivity T c onset of ∼16 K. The fluorine doped samples of the new compound LaRhAsO remain metallic down to 5 K.