Structural phase transition and its critical dynamics from holography

TL;DR

This paper uses holography to model a structural phase transition in a lattice system, revealing critical dynamics, mean-field exponents, and universal scaling laws for kink formation during quenches.

Contribution

It introduces a holographic lattice model in AdS$_3$ capturing the linear-to-zigzag phase transition and analyzes its equilibrium and nonequilibrium critical dynamics.

Findings

Mean-field critical exponents for correlation length and relaxation time.

Universal Kibble-Zurek scaling for kink density in slow quenches.

Breakdown of KZM at fast quenches.

Abstract

We introduce a gravitational lattice theory defined in an AdS$_3$ black hole background that provides a holographic dual description of the linear-to-zigzag structural phase transition, characterized by the spontaneous breaking of parity symmetry observed in, e.g., confined Coulomb crystals. The transition from the high-symmetry linear phase to the broken-symmetry doubly-degenerate zigzag phase can be driven by quenching the coupling between adjacent sites through the critical point. An analysis of the equilibrium correlation length and relaxation time reveals mean-field critical exponents. We explore the nonequilibrium phase transition dynamics leading to kink formation. The kink density obeys universal scaling laws in the limit of slow quenches, described by the Kibble-Zurek mechanism (KZM), and at fast quenches, characterized by a universal breakdown of the KZM.