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تسجيل مستخدم جديدCritical exponent of metal-insulator transition in doped semiconductors: the relevance of the Coulomb interaction
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We report a simulation of the metal-insulator transition in a model of a doped semiconductor that treats disorder and interactions on an equal footing. The model is analyzed using density functional theory. From a multi-fractal analysis of the Kohn-Sham eigenfunctions, we find $ u approx 1.3$ for the critical exponent of the correlation length. This differs from that of Andersons model of localization and suggests that the Coulomb interaction changes the universality class of the transition.
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