  It is found that the polycrystalline NdRu2Ge2 undergoes two successive
magnetic transitions at Tt=10 K and TN=19 K. Evidence of metamagnetic
transition is detected in the magnetization isotherm data in the
antiferromagnetic regime. Temperature dependence of magnetoresistance (MR) show
that the relative magnitudes of MR at TN and Tt change considerably as the
field is increased from 10 kOe to 30 kOe. Moreover, the MR is found to be
positive below 9 K for 30 kOe field although the material is ferromagnetic at
these temperatures. The highest value of negative MR near TN is about 42% in a
field of 30 kOe, while the positive MR is about 35 % at 3 K in a field of 50
kOe. Like MR, the magnetocaloric effect at TN and Tt also shows anomalous
behavior. The relative magnitudes of MCE at these temperatures are found to
change with increase in field. It appears that the high field (>10 kOe)
magnetic state below TN is complex, giving rise to some antiferromagnetic-like
fluctuations, affecting the MR and MCE behavior.

Strongly Correlated Electrons;Materials Science