MESOSCOPIC FLUCTUATIONS OF THE DIPOLE-MOMENT AND THE ELECTRIC POLARIZABILITY

We consider mesoscopic fluctuations of the dipole moment and the elect ric polarizability of a disordered thin film in the diffusive regime. It is shown, that the requirement of a fixed particle number is crucia l for obtaining finite fluctuations at low temperatures. For systems w ith sufficient disorder and a long screening length a spontaneous dipo le moment should be observable with an atomic force microscope.