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arXiv · 1406.7193

A Simple Holographic Model of a Charged Lattice

Francesco Aprile·Takaaki Ishii
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Abstract

We use holography to compute the conductivity in an inhomogeneous charged scalar background. We work in the probe limit of the four-dimensional Einstein-Maxwell theory coupled to a charged scalar. The background has zero charge density and is constructed by turning on a scalar source deformation with a striped profile. We solve for fluctuations by making use of a Fourier series expansion. This approach turns out to be useful for understanding which couplings become important in our inhomogeneous background. At zero temperature, the conductivity is computed analytically in a small amplitude expansion. At finite temperature, it is computed numerically by truncating the Fourier series to a relevant set of modes. In the real part of the conductivity along the direction of the stripe, we find a Drude-like peak and a delta function with a negative weight. These features are understood from the point of view of spectral weight transfer.

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Francesco Aprile, Takaaki Ishii. 2014-07-15. A Simple Holographic Model of a Charged Lattice. https://doi.org/10.1007/jhep10(2014)151

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