394 research outputs found
Under The Dome: Doped holographic superconductors with broken translational symmetry
We comment on a simple way to accommodate translational symmetry breaking
into the recently proposed holographic model which features a superconducting
dome-shaped region on the temperature-doping phase diagram.Comment: 14 pages, 6 figure
S-parameter, Technimesons, and Phase Transitions in Holographic Tachyon DBI Models
We investigate some phenomenological aspects of the holographic models based
on the tachyon Dirac-Born-Infeld action in the AdS space-time. These
holographic theories model strongly interacting fermions and feature dynamical
mass generation and symmetry breaking. We show that they can be viewed as
models of holographic walking technicolor and compute the Peskin-Takeuchi
S-parameter and masses of lightest technimesons for a variety of the tachyon
potentials. We also investigate the phase structure at finite temperature and
charge density. Finally, we comment on the holographic Wilsonian RG in the
context of holographic tachyon DBI models
Phases of holographic superconductors with broken translational symmetry
We consider holographic superconductors in a broad class of massive gravity
backgrounds. These theories provide a holographic description of a
superconductor with broken translational symmetry. Such models exhibit a rich
phase structure: depending on the values of the temperature and the disorder
strength the boundary system can be in superconducting, normal metallic or
normal pseudoinsulating phases. Furthermore the system supports interesting
collective excitation of the charge carriers, which appears in the normal
phase, persists in the superconducting phase, but eventually gets destroyed by
the superconducting condensate. We also show the possibility of building a
phase diagram of a system with the superconducting phase occupying a
dome-shaped region on the temperature-disorder plane.Comment: Minor revisions, interpretation clarified, version published in JHE
On fast quenches and spinning correlators
We study global quantum quenches in a continuous field theoretic system with
UV fixed point. Assuming that the characteristic inverse time scale of the
smooth quench is much larger than all scales inherent to the system except for
the UV-cutoff, we derive the universal scaling behavior of the two-point
correlation functions associated with Dirac fields and spin-1 currents. We
argue that in certain regimes our results can be recovered using the technique
of operator product expansion.Comment: 28 pages, no figure
AdS/CFT and Landau Fermi liquids
We study the field theory dual to a charged gravitational background in which
the low temperature entropy scales linearly with the temperature. We exhibit
the existence of a sound mode which is described by hydrodynamics, even at
energies much larger than the temperature, and explain how this, and other
properties of the field theory, are consistent with those of a
(3+1)-dimensional Landau Fermi liquid, finely tuned to the Pomeranchuk critical
point. We also discuss how one could engineer a higher-derivative gravitational
Lagrangian which reproduces the correct low temperature behavior of shear
viscosity in a generic Landau Fermi liquid.Comment: harvmac, 35 pages, 2 figures. v2: minor changes and references adde
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