Interplay of charge-Density wave and magnetic order in ternary rare-earth nickel carbides, RNiC(R = Pr and Nd)

The electrical and structural properties of NdNiCand PrNiCare examined in single-crystalline samples in order to investigate the interplay of charge-density wave (CDW) and magnetic order in ternary rare-earth nickel carbides, RNiC where R is a rare-earth element. PrNiC(no magnetic order down to 1.5 K) and NdNiC[antiferromagnetic (AF) transition at 17.2 K] show resistance anomalies at 89 and 121 K, respectively, which are revealed to be CDW transitions by observing X-ray satellite reflections. NdNiCalso shows a gradual decrease in both resistivity and CDW amplitude below the Néel temperature. In the AF phase, the magnetoresistance sharply decreases where a ferromagnetic (FM) order occurs, which is realized above the spin-flop magnetic field. These results clearly suggest that the relationships between CDW and magnetic order in RNiCdepend on whether the magnetic order is AF or FM.