Ideally conducting phases in quasi two-dimensional conductors

The possibility of the existence of ideal conductivity at finite temperatures in clean quasi two-dimensional conductors under conditions similar to the quantized Hall effect is discussed. It is found that for metallic electron densities and realistic values of the magnetic field the electronic system should break into two coexisting diamagnetic phases, for which the chemical potential is pinned in the middle of a magnetic energy gap, and the system is nondissipative. The experimental feasibility of the proposed mechanism is briefly discussed.