DENSITY CORRELATIONS OF MAGNETIC-IMPURITIES AND DISORDER

We consider an electron coupled to a random distribution of point vort ices in the plane (magnetic impurities), with a spatial probability di stribution governed by Bose or Fermi statistics at a given temperature . We analyse the effect of the statistics of the magnetic impurities o n the partition Function and the density of states (DOS) of a test par ticle. Comparison is made with the Poisson distribution, i.e. Bose or Fermi statistics at infinite temperature. We show in particular that, for the zero-temperature Fermi distribution. the DOS always exhibits o scillations, whatever the strength of the magnetic disorder, contraril y to the Poissonian case. A diagram describing isolated impurities ver sus Landau level oscillations is proposed.