Regularity and chaos at critical points of first-order quantum phase transitions

TL;DR

This paper investigates the coexistence of regular and chaotic quantum dynamics at the critical point of a first-order quantum phase transition in an interacting boson model, revealing phase-dependent behaviors and spectral characteristics.

Contribution

It provides a detailed classical and quantum analysis of phase-specific dynamics at the critical point, highlighting the persistence of regular rotational bands in the deformed phase.

Findings

Regular dynamics in the deformed phase

Chaotic behavior in the spherical phase

Persistent regular rotational bands in the deformed region

Abstract

We study the interplay between regular and chaotic dynamics at the critical point of a generic first-order quantum phase transition in an interacting boson model of nuclei. A classical analysis reveals a distinct behavior of the coexisting phases in a broad energy range. The dynamics is completely regular in the deformed phase and, simultaneously, strongly chaotic in the spherical phase. A quantum analysis of the spectra separates the regular states from the irregular ones, assigns them to particular phases, and discloses persisting regular rotational bands in the deformed region.