Magnetism near the metal-insulator transition in two-dimensional electron systems: the role of interaction and disorder

Recent thermodynamic measurements on two-dimensional (2D) electron systems have found diverging behavior in the magnetic susceptibility and appearance of ferromagnetism with decreasing electron density. The critical densities for these phenomena coincide with the metal-insulator transition recorded in transport measurements. Based on density functional calculations within the local spin-density approximation, we have investigated the compressibility and magnetic susceptibility of a 2D electron gas in the presence of remote impurities. A correlation between the minimum in the inverse capacitance ($\partial\mu /\partial n$) and the maximum of magnetization and magnetic susceptibility is found. Based on values we obtain for the inverse participation ratio, this seems to be also the MIT point.