关键词: 多体微扰理论, GW近似, 准粒子电子结构, d/f-电子体系, 强关联电子体系

Abstract:

The many-body perturbation theory based on the Green's function provides a rigorous conceptual framework to describe ground-state and excited-state properties of materials. The Green's function depends on the exchange-correlation self-energy, which is the solution of a set of complicated integro-differential equations, named Hedin's equations. The method, which approximates the self-energy by its first-order term in terms of the screened Coulomb interaction (W), is currently the most accurate first-principles approach to describe quasi-particle electronic band structure properties of extended systems. In this review, we first give an overview of the many-body perturbation theory for quasi-particle excitations based on the Green's function and screened Coulomb interaction. The latest methodological developments are reviewed with an attempt to put different newly proposed schemes in a unified framework. The current status of the method, in particular for d/f-electron systems, is illustrated by a few prototypical examples.

Key words: Many-body perturbation theory, GW approximation, Quasi-particle electronic band structure, d/f-electron systems, Strongly correlated electron system