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arXiv · 1010.0682

Strange metals and the AdS/CFT correspondence

Subir Sachdev
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Abstract

I begin with a review of quantum impurity models in condensed matter physics, in which a localized spin degree of freedom is coupled to an interacting conformal field theory in d = 2 spatial dimensions. Their properties are similar to those of supersymmetric generalizations which can be solved by the AdS/CFT correspondence; the low energy limit of the latter models is described by a AdS2 geometry. Then I turn to Kondo lattice models, which can be described by a mean- field theory obtained by a mapping to a quantum impurity coupled to a self-consistent environment. Such a theory yields a 'fractionalized Fermi liquid' phase of conduction electrons coupled to a critical spin liquid state, and is an attractive mean-field theory of strange metals. The recent holographic description of strange metals with a AdS2 x R2 geometry is argued to be related to such mean-field solutions of Kondo lattice models.

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Subir Sachdev. 2010-11-05. Strange metals and the AdS/CFT correspondence. https://doi.org/10.1088/1742-5468%2F2010%2F11%2Fp11022

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