Gapless and gapped holographic phonons
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.
Cite
@article{arxiv.1910.11330,
title = {Gapless and gapped holographic phonons},
author = {Andrea Amoretti and Daniel Areán and Blaise Goutéraux and Daniele Musso},
journal= {arXiv preprint arXiv:1910.11330},
year = {2020}
}
Comments
v1: 24 pages, 10 figures. v2: minor edits, version accepted in jhep