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arXiv · 1009.3966

Zero Sound in Effective Holographic Theories

Bum-Hoon Lee·Da-Wei Pang·Chanyong Park
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Abstract

We investigate zero sound in $D$-dimensional effective holographic theories, whose action is given by Einstein-Maxwell-Dilaton terms. The bulk spacetimes include both zero temperature backgrounds with anisotropic scaling symmetry and their near-extremal counterparts obtained in 1006.2124 [hep-th], while the massless charge carriers are described by probe D-branes. We discuss thermodynamics of the probe D-branes analytically. In particular, we clarify the conditions under which the specific heat is linear in the temperature, which is a characteristic feature of Fermi liquids. We also compute the retarded Green's functions in the limit of low frequency and low momentum and find quasi-particle excitations in certain regime of the parameters. The retarded Green's functions are plotted at specific values of parameters in $D=4$, where the specific heat is linear in the temperature and the quasi-particle excitation exists. We also calculate the AC conductivity in $D$-dimensions as a by-product.

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Bum-Hoon Lee, Da-Wei Pang, Chanyong Park. 2010-09-20. Zero Sound in Effective Holographic Theories. https://doi.org/10.1007/jhep11(2010)120

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