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arXiv · 1910.11330

Gapless and gapped holographic phonons

Andrea Amoretti·Daniel Areán·Blaise Goutéraux·Daniele Musso
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Abstract

We study a holographic model where translations are both spontaneously and explicitly broken, leading to the presence of (pseudo)-phonons in the spectrum. The weak explicit breaking is due to two independent mechanisms: a small source for the condensate itself and additional linearly space-dependent marginal operators. The low energy dynamics of the model is described by Wigner crystal hydrodynamics. In absence of a source for the condensate, the phonons remain gapless, but momentum is relaxed. Turning on a source for the condensate damps and pins the phonons. Finally, we verify that the universal relation between the phonon damping rate, mass and diffusivity reported in arXiv:1812.08118 continues to hold in this model for weak enough explicit breaking.

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Andrea Amoretti, Daniel Areán, Blaise Goutéraux, Daniele Musso. 2019-10-24. Gapless and gapped holographic phonons. https://doi.org/10.1007/jhep01(2020)058

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