Anomalous electrical and magnetic properties of gadolinium hexaboride

TLDR: In this paper, the authors have studied both phases of GdB6 by experimental measurements of electrical resistivity, magnetoresistance, magnetic susceptibility, and Hall effect, and they have shown a large thermal hysteresis associated with the lower phase transition.

Abstract: Gadolinium hexaboride undergoes an antiferromagnetic phase transition below TN≂16 K. A second phase transition takes place below 11 K. We have studied both phases of GdB6 by experimental measurements of electrical resistivity, magnetoresistance, magnetic susceptibility, and Hall effect. The electrical resistivity data show a large thermal hysteresis associated with the lower‐phase transition. Magnetoresistance data in the higher phase is isotropic with respect to sample current and applied magnetic field directions. However, magnetoresistance measurements reveal some unusual behavior in the lower phase, namely, (i) the magnetoresistance is very anisotropic with respect to current and field directions, (ii) a large field hysteresis is observed, and (iii) a field‐induced transition is observed at 4.2 K in a field of ∼7 kOe. This field transition, which is also evident in magnetic susceptibility data, may be due to the formation of a single magnetic domain.