Authors: Johanna Erdmenger Benedikt Herwerth Steffen Klug René Meyer Koenraad Schalm
Publish Date: 2015/05/19
Volume: 2015, Issue: 5, Pages: 94-
Abstract
Within gauge/gravity duality we consider finite density systems in a helical lattice dual to asymptotically antide Sitter spacetimes with Bianchi VII symmetry These systems can become an anisotropic insulator in one direction while retaining metallic be havior in others To this model we add a U1 charged scalar and show that below a critical temperature it forms a spatially homogeneous condensate that restores isotropy in a new superconducting ground state We determine the phase diagram in terms of the helix parameters and perform a stability analysis on its IR fixed point corresponding to a finite density condensed phase at zero temperature Moreover by analyzing fluctuations about the gravity background we study the optical conductivity Due to the lattice this model provides an example for a holographic insulatorsuperfluid transition in which there is no unrealistic deltafunction peak in the normal phase DC conductivity Our results suggest that in the zero temperature limit all degrees of freedom present in the normal phase condense This together with the breaking of translation invariance has implications for Homes’ and Uemuras’s relations This is of relevance for applications to real world condensed matter systems We find a range of parameters in this system where Homes’ relation holdsThis article is published under an open access license Please check the Copyright Information section for details of this license and what reuse is permitted If your intended use exceeds what is permitted by the license or if you are unable to locate the licence and reuse information please contact the Rights and Permissions team
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