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A central role for the exchange-correlation hole in the 2D metal-insulator transition

D. J. W. Geldart·D. Neilson·J. S. Thakur
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Abstract

The 2D metal-insulator transition can be induced either by decreasing the carrier density or by increasing the spin polarization by applying a magnetic field parallel to the plane. Using experimental results for the shift in critical carrier density in an applied field, we show that the two-electron pair correlation function at short distance ($k_Fr\alt2$) has a universal form along the transition line in the magnetic field-carrier density plane. This result provides direct evidence of the central role of Coulomb repulsion and the exchange-correlation hole in driving the metal-insulator transition.

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D. J. W. Geldart, D. Neilson, J. S. Thakur. 2000-10-11. A central role for the exchange-correlation hole in the 2D metal-insulator transition. https://arxiv.org/abs/cond-mat/0010156

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