Two-dimensional electron gas in a uniform magnetic field in the presence of a delta-impurity

R. M. Cavalcanti, C. A. A. de Carvalho

Published 1997-04-17, updated 1999-08-12Version 4

The density of states and the Hall conductivity of a two-dimensional electron gas in a uniform magnetic field and in the presence of a delta impurity are exactly calculated using elementary field theoretic techniques. Although these results are not new, our treatment is explicitly gauge-invariant, and can be easily adapted to other problems involving a delta potential.