PAIRING AND SUPERCONDUCTING PROPERTIES OF 2D FERMI-SYSTEM WITH ATTRACTION

Proceeding from microscopic model Hamiltonian for the system of Fermi- Particles with attraction the effective Lagrangian admitting the analy sis of its superconducting properties at arbitrary fermion concentrati on is obtained. Exact solution of equations for the gap and chemical p otential makes it possible to trace from local pair situation to Coope r pairing and superconductivity of BSC type. The crucial parameter dis criminating the regions of normal and exotic superconducting behaviour s is shown to be that of the energy of two-fermion bound state. The fo rmulas obtained show that in the region of comperatively small concent rations the parameters of 2D-metal correspond to 2nd type superconduct ors.