These notes are based on a series of lectures given at the XV Modave Summer School in September, 2019. The course was organized in five lectures on Holographic techniques applied to condensed matter physics. In order to be self consistent, in the first three lectures I introduced the basic concepts of the so called holographic dictionary. Since...
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2019 (v1)PublicationUploaded on: April 14, 2023
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2015 (v1)Publication
Abstract: We obtain explicit expressions for the thermoelectric transport coefficients of a strongly coupled, planar medium in the presence of an orthogonal magnetic field and momentum-dissipating processes. The computations are performed within the gauge/gravity framework where the momentum dissipation mechanism is introduced by including a...
Uploaded on: April 14, 2023 -
2021 (v1)Publication
Since the 1960s a deep and surprising connection has followed the development of superconductivity and quantum field theory. The Anderson-Higgs mechanism and the similarities between the Dirac and Bogoliubov-de Gennes equations are the most intriguing examples. In this last analogy, the massive Dirac particle is identified with a quasiparticle...
Uploaded on: April 14, 2023 -
2017 (v1)Publication
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...
Uploaded on: April 14, 2023 -
2020 (v1)Publication
In this paper we have considered the 3D Ising model perturbed with the energy operator coupled with a non uniform harmonic potential acting as a trap, showing that this system satisfies the trap-size scaling behavior. Eventually, we have computed the correlators ⟨σ(z)σ(0)⟩, ⟨ϵ(z)ϵ(0)⟩ and ⟨σ(z)ϵ(0)⟩ near the critical point by means of conformal...
Uploaded on: April 14, 2023 -
2019 (v1)Publication
In phases where translations are spontaneously broken, new gapless degrees of freedom appear in the low energy spectrum (the phonons). At long wavelengths, they couple to small fluctuations of the conserved densities of the system. This mixing is captured by new diffusive transport coefficients, as well as qualitatively different collective...
Uploaded on: April 14, 2023 -
2020 (v1)Publication
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...
Uploaded on: April 14, 2023 -
2018 (v1)Publication
We use gauge/gravity duality to write down an effective low energy holographic theory of charge density waves. We consider a simple gravity model which breaks translations spontaneously in the dual field theory in a homogeneous manner, capturing the low energy dynamics of phonons coupled to conserved currents. We first focus on the leading...
Uploaded on: April 14, 2023 -
2019 (v1)Publication
In this Letter, we uncover a universal relaxation mechanism of pinned density waves, combining gauge-gravity duality and effective field theory techniques. Upon breaking translations spontaneously, new gapless collective modes emerge, the Nambu-Goldstone bosons of broken translations. When translations are also weakly broken (e.g., by disorder...
Uploaded on: March 27, 2023