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arXiv · 1112.4669

Fermionic impurities in Chern-Simons-matter theories

Paolo Benincasa·Alfonso V. Ramallo
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Abstract

We study the addition of quantum fermionic impurities to the N=6 supersymmetric Chern-Simons-matter theories in 2+1 spacetime dimensions. The impurities are introduced by means of Wilson loops in the antisymmetric representation of the gauge group. In a holographic setup, the system is represented by considering D6-branes probing the AdS_4 x CP^3 background of type IIA supergravity. We study the thermodynamic properties of the system and show how a Kondo lattice model with holographic dimers can be constructed. By computing the Kaluza-Klein fluctuation modes of the probe brane we determine the complete spectrum of dimensions of the impurity operators. A very rich structure is found, depending both on the Kaluza-Klein quantum numbers and on the filling fraction of the impurities.

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Paolo Benincasa, Alfonso V. Ramallo. 2012-01-10. Fermionic impurities in Chern-Simons-matter theories. https://doi.org/10.1007/jhep02(2012)076

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