Conductance fluctuations at the fractional quantum Hall plateau transitions

We obtain a "mean field" scaling flow of the longitudinal and the Hall cond uctivities in the fractional quantum Hall regime. Using the composite fermi on picture and assuming that the composite fermions follow the Khmelnitskii -Pruisken scaling flow for the integer quantum Hall effect, the unstable fi xed points that govern the transitions between different fractional quantum Hall states are identified. Distributions of the critical longitudinal and Hall conductivities at the unstable fixed points are obtained and implicat ions of the results for the experiments on mesoscopic quantum Hall systems are discussed. [S0163-1829(98)05535-0].