Spin-State Crossover Model for the Magnetism of Iron Pnictides
نویسندگان
چکیده
منابع مشابه
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 quasidegenerate spin states of Fe(2+) ion by intersite electron hoppings, resulting in an effective local spin S(eff). The moments S(eff) tend to form singlet pairs and may condense into a spin nematic phase due to the emergent biquadratic exchange coupli...
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ژورنال
عنوان ژورنال: Physical Review Letters
سال: 2013
ISSN: 0031-9007,1079-7114
DOI: 10.1103/physrevlett.110.207205