ON PECULIARITIES OF SUPERCONDUCTING STATE FORMATION IN 2D METALLIC SYSTEMS

It is shown that the phase diagram of a 2D metal with a varying charge carrier density consists of normal phase regions in which the modulus of the order parameter is zero, the so-called anomalously normal phas e in which it differs from zero but has a random phase, and the Berezi nskii-Kosterlitz-Thouless phase. The characteristic temperatures of tr ansitions between these phases are determined as well as the behavior of the chemical potential as a function of the fermion density and tem perature. An attempt is made to compare qualitatively the obtained pha se diagram with the observed peculiarities in the behavior of underdop ed high-T-c superconducting compounds above their critical temperature . (C) 1997 American Institute of Physics.