title: Electron-Phonon Interactions, Metal-Insulator Transitions, and Holographic Massive Gravity.
abstract: Massive gravity is holographically dual to "realistic" materials with momentum relaxation. The dual graviton potential encodes the phonon dynamics, and it allows for a much broader diversity than considered so far. We construct a simple family of isotropic and homogeneous materials that exhibit an interaction-driven metal-insulator transition. The transition relates to the formation of polarons-phonon-electron quasibound states that dominate the conductivities, shifting the spectral weight above a mass gap. We characterize the polaron gap, width, and dispersion.
authors.affiliation: Departament de Física and IFAE, Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain.
authors.forename: Matteo
authors.initials: M
authors.lastname: Baggioli
authors.affiliation: Departament de Física and IFAE, Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain.
authors.forename: Oriol
authors.initials: O
authors.lastname: Pujolàs