Charge density wave (CDW) and magnetism in RNiC₂ family (R = rare earth metal)

The ternary rare-earth nickel dicarbides RNiC₂ (R - rare earth metal) with a non-centrosymmetric, orthorhombic crystal structure offer a unique opportunity to tune the ground state with varying R atom. The charge density wave (CDW) has been found for most of the members of the RNiC₂ family (R = Pr − Lu) with the Peierls temperature scaling linearly with the unit-cell volume. LaNiC₂ compound is an unconventional superconductor, SmNiC₂ undergoes a ferromagnetic transition and the rest of the compounds (apart from nonmagnetic YNiC₂ and LuNiC₂ exhibiting large positive magnetoresistance and PrNiC₂ where only a weak magnetic anomaly is observed) order antiferromagnetically below 25 K.
In this presentation, the large diversity of physical phenomena occurring in the RNiC₂ family will be discussed in terms of relations between various types of ordering on the basis of magnetic, transport and galvanomagnetic measurements. The main emphasis will be put on the CDW mutually interacting with magnetism in the polycrystalline RNiC₂ and their solid solutions.