Mixed configurations and intertwined quantum phase transitions in odd-mass nuclei

TL;DR

This paper introduces a new theoretical framework to study spectral properties and quantum phase transitions in odd-mass nuclei, revealing the coexistence of different types of phase transitions and their interplay.

Contribution

A novel Bose-Fermi model that captures configuration mixing and intertwined quantum phase transitions in odd-mass nuclei.

Findings

Identification of Type II QPTs involving state crossings.

Observation of gradual shape evolution within intruder configurations.

First demonstration of intertwined QPTs in odd-mass nuclei.

Abstract

We introduce a new Bose-Fermi framework for studying spectral properties and quantum phase transitions (QPTs) in odd-mass nuclei, in the presence of configuration mixing. A detailed analysis of odd-mass Nb isotopes discloses the effects of an abrupt crossing of states in normal and intruder configurations (Type II QPT), accompanied by a gradual evolution from spherical- to deformed-core shapes within the intruder configuration (Type I QPT). The pronounced presence of both types of QPTs demonstrates, for the first time, the occurrence of intertwined QPTs in odd-mass nuclei.