The results of magnetization, magnetic susceptibility $\left(\chi \right),$ electrical measurements, and magnetoresistance measurements as a function of temperature (2–300 K) in the single-crystalline ${\mathrm{Dy}}_2{\mathrm{PdSi}}_3$ are reported for two different directions ([0001] and $\left[101¯0\right])$ of the crystal. The results reveal that there is an onset of magnetic ordering below 8 K. The high-temperature paramagnetic Curie temperature is positive for both directions, though antiferromagnetic coupling dominates in the basal plane; the magnetic coupling along the c axis is of a ferromagnetic type. The electrical resistance data for both the directions indicate the formation of magnetic Brillouin-zone boundary gaps. A finding of importance is that the broad peak in the temperature dependent $\chi$ around 50 K noted for the analogous Tb compound is not observed in the present investigations, though there is a weak difference between the zero-field-cooled and field-cooled $\chi$ versus T curves below 40 K (the implications of which are not clear at present). The results establish that this compound exhibits giant magnetoresistance behavior at low temperatures. We also compare the observed anisotropic behavior with those in Tb and Gd compounds.

• Received 11 December 2000

DOI:https://doi.org/10.1103/PhysRevB.64.012418