Anomalous classical diffusion of high mobility 2D electron gas in magnetic field

It is well known that in a classically strong magnetic field, ωcτt1 (ωc is the cyclotron frequency and τt is the transport relaxation time), the transverse conductivity is inversely proportional to magnetic field squared, σxx=σ0/(ωcτt)2, wher σ0 is the conductivity without magnetic field. Such a dependence results from the lack of correlation of scattering events of an electron. This condition can be violated in a high mobility 2D gas, where the correlation length of the scattering potential is large. A strong correlation between scattering events results in an anomalous dependence of σxx on magnetic field.