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

S. M. Fazeli·K. Esfarjani·B. Tanatar
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Abstract

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 ($\partialμ/\partial n$) 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.

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S. M. Fazeli, K. Esfarjani, B. Tanatar. 2006-02-18. Magnetism near the metal-insulator transition in two-dimensional electron systems: the role of interaction and disorder. https://arxiv.org/abs/cond-mat/0602434

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