Low-temperature specific heat for ferromagnetic and antiferromagnetic   orders in CaRu1-xMnxO3
  Low-temperature specific heat of CaRu1-xMnxO3 was measured to clarify the role of d electrons in ferromagnetic and antiferromagnetic orders observed above x=0.2. Specific heat divided by temperature C_p/T is found to roughly follow a T^2 function, and relatively large magnitudes of electronic specific heat coefficient gamma were obtained in wide x range. In particular, gamma is unchanged from the value at x=0 (84 mJ/K^2 mol) in the paramagnetic state for x<=0.1, but linearly reduced with increasing x above x= 0.2. These features of gamma strongly suggest that itinerant d electrons are tightly coupled with the evolution of magnetic orders in small and intermediate Mn concentrations. 
M. Yokoyama, S. Nakano, S. Someya, T. Nakada, N. Wada, H. Kawanaka, H.   Bando, K. Tenya, A. Kondo, K. Kindo
cond-mat.str-el