  In the framework of a 2D Fermi-gas with short-range repulsive interaction we
find the critical temperature of the superfluid phase transition based on
Kohn-Luttinger effect, and analyze its dependence on magnetic field. We
calculate strong-coupling corrections to the Ginzburg-Landau free energy
functional and analyze the staibility of 2D superfluid phases. Possible
applications of the results to real systems are discussed.
