Generalized entanglement in static and dynamic quantum phase transitions

TL;DR

This paper studies entanglement in exactly solvable 1D XY spin models with alternating magnetic fields, revealing how entanglement characterizes static phase transitions and exhibits universal scaling during slow quenches.

Contribution

It introduces a Lie-algebraic generalized entanglement measure that accurately captures phase diagrams and dynamical scaling in quantum phase transitions of these models.

Findings

Entanglement faithfully portraits static phase diagram including different order transitions.

Universal dynamical scaling of entanglement observed during slow quenches.

Lie-algebraic measure effectively characterizes quantum critical phenomena.

Abstract

We investigate a class of one-dimensional, exactly solvable anisotropic XY spin-1/2 models in an alternating transverse magnetic field from an entanglement perspective. We find that a physically motivated Lie-algebraic generalized entanglement measure faithfully portraits the static phase diagram -- including second- and fourth-order quantum phase transitions belonging to distinct universality classes. In the simplest time-dependent scenario of a slow quench across a quantum critical point, we identify parameter regimes where entanglement exhibits universal dynamical scaling relative to the static limit.