A holographic perspective on phonons and pseudo-phonons

作者：Amoretti Andrea^*; Arean Daniel; Argurio Riccardo; Musso Daniele; Zayas Leopoldo A Pando

来源：The Journal of High Energy Physics, 2017, 2017(5): 051.

DOI：10.1007/JHEP05(2017)051

• AdS-CFT Correspondence
• Effective Field Theories
• Holography and condensed matter physics (AdS/CMT)

We analyze the concomitant spontaneous breaking of translation and conformal symmetries by introducing in a CFT a complex scalar operator that acquires a spatially dependent expectation value. The model, inspired by the holographic Q-lattice, provides a privileged setup to study the emergence of phonons from a spontaneous translational symmetry breaking in a conformal field theory and offers valuable hints for the treatment of phonons in QFT at large. We first analyze the Ward identity structure by means of standard QFT techniques, considering both spontaneous and explicit symmetry breaking. Next, by implementing holographic renormalization, we show that the same set of Ward identities holds in the holographic Q-lattice. Eventually, relying on the holographic and QFT results, we study the correlators realizing the symmetry breaking pattern and how they encode information about the low-energy spectrum.

• 出版日期2017-5-10