Hall conductivity as the topological invariant in phase space in the presence of interactions and non-uniform magnetic field
C. X. Zhang +, M. A. Zubkov+*
+Physics Department, Ariel University, 40700 Ariel, Israel
*Institute for Theoretical and Experimental Physics, 117259 Moscow, Russia
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. 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 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