Fermionic impurities in Chern-Simons-matter theories

TL;DR

This paper investigates fermionic impurities in 3D supersymmetric Chern-Simons-matter theories using holography, revealing complex impurity spectra and thermodynamic behaviors through D-brane probe analysis.

Contribution

It introduces a holographic model of fermionic impurities via D6-branes in AdS_4 x CP^3, analyzing their spectrum and thermodynamics.

Findings

Constructed a holographic Kondo lattice model with dimers.

Computed the complete spectrum of impurity operator dimensions.

Discovered a rich structure depending on quantum numbers and impurity filling fraction.

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.