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arXiv · 1203.4908

Hawking Radiation and Non-equilibrium Quantum Critical Current Noise

Julian Sonner·Andrew G. Green
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Abstract

The dynamical scaling of quantum critical systems in thermal equilibrium may be inherited in the driven steady-state, leading to universal out-of-equilibrium behaviour. This attractive notion has been demonstrated in just a few cases. We demonstrate how holography - a mapping between the quantum critical system and a gravity dual - provides an illuminating perspective and new results. Non-trivial out-of-equilibrium universality is particularly apparent in current noise, which is dual to Hawking radiation in the gravitational system. We calculate this in a 2-dimensional system driven by a strong in-plane electric field and deduce a universal scaling function interpolating between previously established equilibrium and far-from-equilibrium current noise. Since this applies at all fields, out-of-equilibrium experiments no longer require very high fields for comparison with theory.

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Julian Sonner, Andrew G. Green. 2012-08-20. Hawking Radiation and Non-equilibrium Quantum Critical Current Noise. https://doi.org/10.1103/physrevlett.109.091601

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