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arXiv · 1008.4134

Non-linear, Finite Frequency Quantum Critical Transport from AdS/CFT

Andreas Karch·S. L. Sondhi
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Abstract

Transport at a quantum critical point depends sensitively on the relative magnitudes of temperature, frequency and electric field. Here we used the gauge/gravity correspondence to compute the full temperature and, generally nonlinear, electric field dependence of the electrical conductivity for some model critical theories. In the special case of 2+1 dimensions we are also able to find the full time-dependent response of the system to an arbitrary time dependent external electric field. The response of the system is instantaneous, implying a frequency independent conductivity. We describe a mechanism that rationalizes the instantaneous response.

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Andreas Karch, S. L. Sondhi. 2011-01-26. Non-linear, Finite Frequency Quantum Critical Transport from AdS/CFT. https://doi.org/10.1007/jhep01(2011)149

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