Finkel'stein nonlinear sigma model: interplay of disorder and interaction in 2D electron systems

In this paper I briefly review recent theoretical results derived within the Finkel'stein nonlinear sigma model approach for description of 2D interacting disordered electron systems. The examples include an electron system with two valleys, electrons in a double quantum well, electrons on the surface of a topological insulator, an electron system with superconducting correlations, and the integer quantum Hall effect.