Orbital phase transition in 2-d pyrochlore
نویسندگان
چکیده
We present here correlation driven orbital Mott transition in 2 dimensional pyrochlore lattice. We study a model Hamiltonian in which we take Hund’s coupling between itinerant and localized electrons apart from the coulomb interaction. In the weak coupling limit, we calculate zero temperature susceptibility under random phase approximation and find the model in para orbital phase. In strong coupling limit, we calculate the effective Hamiltonian using Green function perturbation theory and find out ferro-orbital ordering at zero temperature. Finally, we use a static auxiliary field based Monte Carlo, explicitly retaining all the spatial correlations, to study finite temperature phase diagram of the model.
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