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arXiv · 1711.05972

Dielectric response of Anderson and pseudogapped insulators

M. V. Feigel'man·D. A. Ivanov·E. Cuevas
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Abstract

Using a combination of analytic and numerical methods, we study the polarizability of a (non-interacting) Anderson insulator in one, two, and three dimensions and demonstrate that, in a wide range of parameters, it scales proportionally to the square of the localization length, contrary to earlier claims based on the effective-medium approximation. We further analyze the effect of electron-electron interactions on the dielectric constant in quasi-1D, quasi-2D and 3D materials with large localization length, including both Coulomb repulsion and phonon-mediated attraction. The phonon-mediated attraction (in the pseudogapped state on the insulating side of the Superconductor-Insulator Transition) produces a correction to the dielectric constant, which may be detected from a linear response of a dielectric constant to an external magnetic field.

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M. V. Feigel'man, D. A. Ivanov, E. Cuevas. 2017-11-16. Dielectric response of Anderson and pseudogapped insulators. https://doi.org/10.1088/1367-2630%2Faac0d7

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