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Anisotropic Metal-Insulator Transition in Epitaxial Thin Films

I. B. Altfeder·X. Liang·D. M. Chen·V. Narayanamurti
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Abstract

Quantum wells made of simple polyvalent metals represent a novel family of doped 2D Mott-Hubbard insulators. As scanning tunneling microscopy experiments show, these systems exhibit an anisotropic form of metal-insulator transition. Their elementary excitations possess coherent wave-like properties along the normal axis, and show an incoherent behavior in-plane. The development of such an anisotropic coherence is most likely related to Coulomb interaction between localized and delocalized thin film electronic states - 2D Kondo screening.

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I. B. Altfeder, X. Liang, D. M. Chen, V. Narayanamurti. 2003-11-04. Anisotropic Metal-Insulator Transition in Epitaxial Thin Films. https://doi.org/10.1103/physrevlett.92.226404

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