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arXiv · 1412.8346

Thermoelectric conductivities, shear viscosity, and stability in an anisotropic linear axion model

Xian-Hui Ge·Yi Ling·Chao Niu·Sang-Jin Sin
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Abstract

We study thermoelectric conductivities and shear viscosities in a holographically anisotropic model, which is dual to a spatially anisotropic $\mathcal{N}=4$ super-Yang-Mills theory at finite chemical potential. Momentum relaxation is realized through perturbing the linear axion field. Ac conductivity exhibits a coherent/incoherent metal transition. Deviations from the Wiedemann-Franz law are also observed in our model. The longitudinal shear viscosity for prolate anisotropy violates the bound conjectured by Kovtun-Son-Starinets. We also find that thermodynamic and dynamical instabilities are not always equivalent by examining the Gubser-Mitra conjecture.

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Xian-Hui Ge, Yi Ling, Chao Niu, Sang-Jin Sin. 2015-11-16. Thermoelectric conductivities, shear viscosity, and stability in an anisotropic linear axion model. https://doi.org/10.1103/physrevd.92.106005

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