Regular and chaotic classical dynamics in the U(5)-SU(3) quantum phase transition of the IBM

TL;DR

This paper investigates the classical dynamics during a quantum phase transition in the interacting boson model, revealing chaotic behavior in the spherical phase and regular dynamics in the deformed phase, with both coexisting in the transition region.

Contribution

It provides a detailed analysis of the classical dynamics across the U(5)-SU(3) transition, highlighting the coexistence of chaos and regularity in different phases.

Findings

Chaotic dynamics in the spherical phase resemble Hénon-Heiles type.

Regular dynamics are observed in the deformed phase, sensitive to local degeneracies.

Both chaotic and regular dynamics coexist in the transition region, creating a divided phase space.

Abstract

We study the classical dynamics in a generic first-order quantum phase transition between the U(5) and SU(3) limits of the interacting boson model. The dynamics is chaotic, of H\'enon-Heiles type, in the spherical phase and is regular, yet sensitive to local degeneracies, in the deformed phase. Both types of dynamics persist in the coexistence region resulting in a divided phase space.