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arXiv · 0801.1693

Impure AdS/CFT

Sean A. Hartnoll·Christopher P. Herzog
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Abstract

We study momentum relaxation due to dilute, weak impurities in a strongly coupled CFT, a truncation of the M2 brane theory. Using the AdS/CFT correspondence, we compute the relaxation time scale as a function of the background magnetic field B and charge density ρ. The theory admits two different types of impurities. We find that for magnetic impurities, momentum relaxation due to the impurity is suppressed by a background B or ρ. For electric impurities, due to an underlying instability in the theory towards an ordered phase, the inverse relaxation time scale increases dramatically near \sqrt{B^2 + ρ^2/σ^2_0} \sim 21 T^2. We compute the Nernst response for the impure theory, and comment on similarities with recent measurements in superconductors.

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Sean A. Hartnoll, Christopher P. Herzog. 2008-02-14. Impure AdS/CFT. https://doi.org/10.1103/physrevd.77.106009

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