Quasiclassical approach to impurity effect on magnetooscillations in 2D metals

We develop a quasiclassical method based on the path integral formalism, to study the influence of disorder on magnetooscillations of the density of states and conductivity. The treatment is appropriate for electron systems in the presence of a random potential with large correlation length or a random magnetic field, which are characterisitic features of various 2D electronic systems presently studied in experiment. In particular, we study the system of composite fermions in the fractional quantum Hall effect device, which are coupled to the Chern--Simons field and subject to a long--range random potential.