Publications (10)0 Total impact
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ABSTRACT: We investigate fermion self energy problem in the strongly coupled dense
medium in holographic approach. By working out bottom up models as well as top
down ones we showed that vanishing thermal mass and non-existence of
temperature generated plasmino mode is the universal feature of the strongly
interacting fermion system. We identified that the dual of the bulk Rashiba
effect, which was recently found by the Herzog et.al, is the presence of the
plasmino mode generated by the density.
05/2013;
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ABSTRACT: We consider the self-energy of strongly interacting fermions in the medium
using gauge/gravity duality of $D4/D8$ system. We study the mass generation of
the thermal and/or dense medium and the collective excitation called plasmino,
by considering the spectral function of fermion and its dispersion relation.
Our results are very different from those of the hard thermal loop method: for
zero density, there is no thermal mass or plasmino in any phase. Plasmino in
deconfined phase is not allowed in $D4/D8$ set up. In the confined phase, there
is plasmino modes only for a window of density.
05/2012;
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ABSTRACT: We consider the hydrodynamics of strongly interacting quark gluon plasma in
finite temperature and density using the holographic duality of charged black
hole in anti DeSitter space. We calculate the transport coefficients at
arbitrary energy scale by considering the holographic screen at finite radial
position. We first calculate the flow of sound velocity in this method and
check the consistence with previous result. Then we calculate diffusion
constant of charge and find that Einstein relation between susceptibility,
conductivity and diffusion constant will hold at arbitrary slice.
04/2012;
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ABSTRACT: We consider quark-gluon plasma with chemical potential and study
renormalization group flows of transport coefficients in the framework of
gauge/gravity duality. We first study them using the flow equations and compare
the results with hydrodynamic results by calculating the Green functions on the
arbitrary slice. Two results match exactly. Transport coefficients at arbitrary
scale is ontained by calculating hydrodynamics Green functions. When either
momentum or charge vanishes, transport coefficients decouple from each other.
09/2011;
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ABSTRACT: We study the relations between two different approaches to the holographic
Renormalization Group (RG) flow at the dual gravity level: One is the radial
evolution of the classical equation of motion and the other is the flow
equation given by the holographic Wilsonian RG coming from the cut off
independence. Apparently, the two flows look different. We give general proofs
that the two flows are actually equivalent. The role of the momentum continuity
(MC) is essential. We show that MC together with cutoff independence gives the
evolution equation of the boundary values. Equivalence of conductivity flows in
two paradigm has been shown as an explicit example. We also get the connecting
formula of Green functions and AC conductivity at arbitrary slice in terms of
its value at horizon for various geometry backgrounds.
02/2011;
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ABSTRACT: We consider the gravity dual of strongly coupled system at a Lifshitz-fixed
point and finite temperature, which was constructed in a recent work
arXiv:0909.0263. We construct an Abelian Higgs model in that background and
calculate condensation and conductivity using holographic techniques. We find
that condensation happens and DC conductivity blows up when temperature turns
below a critical value.
09/2009;
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ABSTRACT: We consider a black hole solution with a non-trivial dilaton from IIB super gravity which is expected to describe a strongly coupled hot gauge plasma with non-vanishing gluon condensation present. We construct a rotating and moving baryon to probe the screening and phases of the plasma. Melting of the baryons in hot plasma in this background had been studied previously, however, we show that baryons melt much lower temperature than has been suggested previously. Comment: 3 figures, 12 pages
07/2009;
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ABSTRACT: We propose a Dirac-Born-Infeld (DBI) D5 vertex brane plus N_c fundamental strings configuration to describe a baryon probe in strongly coupled gauge theory with gluon condensation at finite temperature via AdS/CFT correspondence. We investigate properties of this configuration in a dilaton deformed AdS_5\times S^5 background, in which IIB string theroy is dual to super Yang-Mills thery in a state with a constant self-dual gauge field (F_{mn}=F^*_{mn}) background. We find that for most values of temperature T and gluon condensation parameter q (q = \pi^2<F_{mn}F_{mn}>), there always exists a screening length L_s. The relation L_s\sim{1\ov T} has been checked. We give the q dependence of L_s. We calculate the boost velocity v(v=-\tanh\eta) and angular velocity \omega dependence of L_s for a baryon probe, and obtain L_s=L_0*(1-v^2)^{1/4} for large v and L_s\sim\omega^{-1}, which are consistent with those dependence relations in the point brane plus strings case, and find that the usual relations have been modified by q. We also calculate the mass of baryon and find T dependence of baryon mass. Comment: 16 pages, 7 figures, published version on JHEP
04/2009;
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ABSTRACT: We build a holographic description of non-relativistic system for superconductivity in strongly interacting condensed matter via gauge/gravity duality. We focus on the phase transition and give an example to show that a simple gravitational theory can provide a non-relativistic holographical dual description of a superconductor. There is also a critical temperature like the relativistic case, below which a charged condensation field appears by a second order phase transition and the (DC) conductivity becomes infinite. We also calculated the frequency dependent conductivity. Comment: 12 pages, 5 figures, non-relativistic parameter dependence of critical temperature was added
03/2009;
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ABSTRACT: We consider a strings-junction holographic model of probe baryon in the finite-temperature supersymmetric Yang-Mills dual of the AdS-Schwarzschild black hole background. In particular, we investigate the screening length for high spin baryon composed of rotating N_c heavy quarks. To rotate quarks by finite force, we put hard infrared cutoff in the bulk and give quarks finite mass. We find that N_c microscopic strings are embedded reasonably in the bulk geometry when they have finite angular velocity \omega, similar to the meson case. By defining the screening length as the critical separation of quarks, we compute the \omega dependence of the baryon screening length numerically and obtain a reasonable result which shows that baryons with high spin dissociate more easily. Finally, we discuss the relation between J and E^2 for baryons. Comment: 18 pages, 19 figures, version to appear in JHEP
05/2008;
