Slightly nonideal 2D Fermi gas in a magnetic field
Bychkov Yu. A. , Kolesnikov A. V.
The properties of a slightly nonideal 2D Fermi gas in a magnetic field are analyzed by a Feynman-diagram technique. Expressions for the eigenenergy part of the one-particle Green's function are derived in up to second-order perturbation theory. Because the spectrum of the 2D particles is discrete in a magnetic field, there is no attenuation of the quasiparticles, and there is a splitting of seed Landau levels. The eigenenergy part has a pole at zero frequency. The maximum filling factor for each sublevel is