Evolution of ferromagnetic order in URhGe alloyed with Ru, Co and Si

Abstract We have investigated the evolution of ferromagnetic order in the correlated metal URhGe (Curie temperature T C = 9.5 K) by chemical substitution of Ru, Co and Si. Polycrystalline samples URh 1− x Ru x Ge ( x ≤ 0.6 ), URh 1− x Co x Ge ( x ≤ 0.9 ) and URhGe 1− x Si x ( x ≤ 0.2 ) have been prepared and the magnetic properties have been investigated by magnetization and transport experiments. In the case of Ru doping, T C initially increases, but then decreases linearly as a function of x and is completely suppressed for x cr ≈ 0.38 . The Curie temperature in the URh 1− x Co x Ge series has a broad maximum T C = 20 K near x = 0.6 and then drops to 8 K for x = 0.9 . In the case of Si doping T C stays roughly constant. We conclude that the alloy systems URh 1− x Ru x Ge and URh 1− x Co x Ge are interesting candidates to study the ferromagnetic instability.