TY  - JOUR
A1  - Erdmenger, Johanna
A1  - Hoyos, Carlos
A1  - O'Bannon, Andy
A1  - Papadimitriou, Ioannis
A1  - Probst, Jonas
A1  - Wu, Jackson M.S.
T1  - Two-point functions in a holographic Kondo model
T2  - Journal of High Energy Physics
N2  - We develop the formalism of holographic renormalization to compute two-point functions in a holographic Kondo model. The model describes a (0 + 1)-dimensional impurity spin of a gauged SU(N ) interacting with a (1 + 1)-dimensional, large-N , strongly-coupled Conformal Field Theory (CFT). We describe the impurity using Abrikosov pseudo-fermions, and define an SU(N )-invariant scalar operator O built from a pseudo-fermion and a CFT fermion. At large N the Kondo interaction is of the form O\(^{†}\)O, which is marginally relevant, and generates a Renormalization Group (RG) flow at the impurity. A second-order mean-field phase transition occurs in which O condenses below a critical temperature, leading to the Kondo effect, including screening of the impurity. Via holography, the phase transition is dual to holographic superconductivity in (1 + 1)-dimensional Anti-de Sitter space. At all temperatures, spectral functions of O exhibit a Fano resonance, characteristic of a continuum of states interacting with an isolated resonance. In contrast to Fano resonances observed for example in quantum dots, our continuum and resonance arise from a (0 + 1)-dimensional UV fixed point and RG flow, respectively. In the low-temperature phase, the resonance comes from a pole in the Green’s function of the form −i〈O〉\(^{2}\), which is characteristic of a Kondo resonance.
KW  - holography and condensed matter physics (AdS/CMT)
KW  - AdS-CFT Correspondence
KW  - gauge-gravity correspondence
Y1  - 2017
UR  - https://opus.bibliothek.uni-wuerzburg.de/frontdoor/index/index/docId/17113
UR  - https://nbn-resolving.org/urn:nbn:de:bvb:20-opus-171139
VL  - 3
IS  - 39
ER  -