Hall conductivity as the topological invariant in phase space in the presence of interactions and non-uniform magnetic field

Abstract: The quantum Hall conductivity in the presence of constant magnetic field may be represented as the topological TKNN invariant. Recently the generalization of this expression has been proposed for the non - uniform magnetic field. \rev{The quantum Hall conductivity is represented as the topological invariant in phase space in terms of the Wigner transformed two - point Green function.} This representation has been derived when the inter - electron interactions were neglected. It is natural to suppose, that in the presence of interactions the Hall conductivity is still given by the same expression, in which the non - interacting Green function is substituted by the complete two - point Green function \rev{ including the interaction contributions}. We prove this conjecture within the framework of the $2+1$ D tight - binding model of rather general type using the ordinary perturbation theory.