Holographic quantum matter

TL;DR

This paper reviews holographic duality approaches to understanding quantum matter without quasiparticles, covering theories, transport phenomena, symmetry breaking, and non-equilibrium dynamics with connections to experiments.

Contribution

It provides a comprehensive overview of holographic models of non-quasiparticle quantum matter, including transport and symmetry-breaking phenomena, with new insights into their theoretical and experimental relevance.

Findings

Holographic duality models can describe non-quasiparticle quantum states.

Transport in such states can be analyzed using memory matrix and hydrodynamics.

The review connects holographic theories to experimental quantum materials.

Abstract

We present a review of theories of states of quantum matter without quasiparticle excitations. Solvable examples of such states are provided through a holographic duality with gravitational theories in an emergent spatial dimension. We review the duality between gravitational backgrounds and the various states of quantum matter which live on the boundary. We then describe quantum matter at a fixed commensurate density (often described by conformal field theories), and also compressible quantum matter with variable density, providing an extensive discussion of transport in both cases. We present a unified discussion of the holographic theory of transport with memory matrix and hydrodynamic methods, allowing a direct connection to experimentally realized quantum matter. We also explore other important challenges in non-quasiparticle physics, including symmetry broken phases such as superconductors and non-equilibrium dynamics.