374 research outputs found
Thermoelectric DC conductivities with momentum dissipation from higher derivative gravity
We present a mechanism of momentum relaxation in higher derivative gravity by
adding linear scalar fields to the Gauss-Bonnet theory. We analytically
computed all of the DC thermoelectric conductivities in this theory by adopting
the method given by Donos and Gauntlett in [arXiv:1406.4742]. The results show
that the DC electric conductivity is not a monotonic function of the effective
impurity parameter : in the small limit, the DC conductivity is
dominated by the coherent phase, while for larger , pair creation
contribution to the conductivity becomes dominant, signaling an incoherent
phase. In addition, the DC heat conductivity is found independent of the
Gauss-Bonnet coupling constant.Comment: 1+19 pages, 2 figures,typos in Eq.(40) correcte
Anisotropic plasma with a chemical potential and scheme-independent instabilities
Generically, the black brane solution with planar horizons is
thermodynamically stable. We find a counter-example to this statement by
demonstrating that an anisotropic black brane is unstable. We present a charged
black brane solution dual to a spatially anisotropic finite temperature
super Yang-Mills plasma at finite chemical potential.
This static and regular solution is obtained both numerically and analytically.
We uncover rich thermodynamic phase structures for this system by considering
the cases when the anisotropy constant "a" takes real and imaginary values,
respectively. In the case , the phase structure of this anisotropic
black brane is similar to that of Schwarzschild-AdS black hole with
horizon topology, yielding a thermodynamical instability at smaller horizon
radii. For the condition , the thermodynamics is dominated by the
black brane phase for all temperatures.Comment: 14pages,14figures, minor changes, PLB in pres
Canonical interpretation of and in the family
Inspired by the new resonance , we calculate the masses and
two-body OZI-allowed strong decays of the higher vector bottomonium sates
within both screened and linear potential models. We discuss the possibilities
of and as mixed states via the mixing. Our
results suggest that and might be explained as
mixed states between - and -wave vector states. The
and resonances may correspond to the mixed states
dominated by the - and -wave components, respectively. The mass and the
strong decay behaviors of the resonance are consistent with
the assignment of the state in the potential models.Comment: 9 pages, 4 figures. More discussions are adde
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