Diagrammatic quantum field formalism for localized electrons

Article

关键词: SYSTEM-SIZE;    METALS;    GAS;   

DOI  :  10.1103/PhysRevB.78.195117

来源: SCIE

【 摘 要 】

We introduce a diagrammatic quantum field formalism for the evaluation of normalized expectation values of operators, and suitable for systems with localized electrons. It is used to develop a convergent series expansion for the energy in powers of overlap integrals of single-particle orbitals. This method gives intuitive and practical rules for writing down the expansion to arbitrary order of overlap and can be applied to any spin configuration and to any dimension. Its applicability for systems with well-localized electrons is illustrated with examples, including the two-dimensional Wigner crystal and spin singlets in the low-density electron gas.

【 授权许可】

Free