Spin-State Crossover Model for the Magnetism of Iron Pnictides
Spin-State Crossover Model for the Magnetism of Iron Pnictides
We propose a minimal model describing magnetic behavior of Fe-based superconductors. The key ingredient of the model is a dynamical mixing of quasi-degenerate spin states of Fe2+ ion by intersite electron hoppings, resulting in an effective local spin Seff. The moments Seff tend to form singlet pairs, and may condense …