Origin of the Heavy Fermion Behavior in Ca_{2-x}Sr_{x}RuO_{4}: Roles of Coulomb Interaction and the Rotation of RuO_{6} octahedra

Naoya Arakawa, Masao Ogata

We study the electronic states for Ca_{2-x}Sr_{x}RuO_{4} in $0.5\le x\le 2$ within the Gutzwiller approximation (GA) on the basis of the three-orbital Hubbard model for the Ru t…