Entanglement study in the island of inversion region using an ab initio approach
Phys. Rev. C 113, 064307 – Published 4 June, 2026
DOI: https://doi.org/10.1103/m66g-vtqq
Abstract
Quantum entanglement provides a unique perspective for probing nuclear structure. In this work, we employ quantum entanglement measures, including proton-neutron entanglement entropy, mutual information, and quantum relative entropy, to investigate the evolution of entanglement patterns as we approach neutron-rich nuclei. The study is carried out in the vicinity of the island of inversion region consisting of even- Ne, Mg, and Si isotopes, and also for isotones corresponding to . The state-of-the-art ab initio valence space in-medium similarity renormalization group method is used for this purpose. We highlight the role of proton-neutron entanglement entropy in the formation of the island of inversion region. Mutual information provides insight into the strength of correlations between proton-proton, neutron-neutron, and proton-neutron single-particle states. While these correlations are relatively weak between protons and neutrons in the ground states, they become comparable to like-particle correlations in excited states. The quantum relative entropy is also studied between and states of the Ne, Mg, and Si isotopes, as well as isotones, using the Kullback-Leibler divergence and Jensen-Shannon divergence. We perform these calculations by expressing the nuclear wave functions in a Slater-determinant basis and analyzing them through complementary partitions, including proton-neutron and mode-resolved factorizations.