Sd-model with strong exchange coupling and a metal-insulator phase transition

Condensed Matter Physics

关键词: Kondo lattice model;    strongly correlated electron systems;    metal-insulator phase transitions;   

DOI  :  10.5488/CMP.9.3.545

来源: DOAJ

【 摘 要 】

Sd-exchange model (Kondo lattice model) is formulated for strong sd-coupling within the framework of the X-operators technique and the generating functional approach. The X-operators are constructed based on the exact eigen functions of a single-site sd-exchange Hamiltonian. Such representation enables us to develop a perturbation theory near the atomic level. A locator-type representation was derived for the electron Green's function. The electron self-energy includes interaction of electrons and spin fluctuations. An integral equation for the self-energy was obtained in the limit of infinite localized spins. A solution of this equation in the static approximation for spin fluctuations leads to a structure of electron Green's function showing a metal-insulator phase transition. This transition is similar to that in the Hubbard model at half filling.

【 授权许可】

Unknown