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arXiv · 1207.0819

Physical Response Functions of Strongly Coupled Massive Quantum Liquids

Bum-Hoon Lee·Xiaojian Bai·Matthias C. Wapler
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Abstract

We study physical properties of strongly coupled massive quantum liquids from their spectral functions using the AdS/CFT correspondence. The generic model that we consider is dense, heavy fundamental matter coupled to SU(N_c) super Yang-Mills theory at finite temperature above the deconfinement phase transition but below the scale set by the baryon number density. In this setup, we study the current-current correlators of the baryon number density using new techniques that employ a scaling behavior in the dual geometry. Our results, the AC conductivity, the quasi-particle spectrum and the Drude-limit parameters like the relaxation time are simple temperature-independent expressions that depend only on the mass-squared to density ratio and display a crossover between a baryon- and meson-dominated regime. We concentrated on the (2+1)-dimensional defect case, but in principle our results can also be generalized straightforwardly to other cases.

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Bum-Hoon Lee, Xiaojian Bai, Matthias C. Wapler. 2012-09-06. Physical Response Functions of Strongly Coupled Massive Quantum Liquids. https://doi.org/10.1007/jhep10(2012)015

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