2021/12/31 by J. Kovács, Kovács, J., A. T. Kruppa +7 · 4 citations
Chemistry · #Advanced NMR Techniques and Applications #Chemical Physics (physics.chem-ph) #FOS: Physical sciences #Nuclear Theory (nucl-th) #Strongly Correlated Electrons (cond-mat.str-el)
paper · pdf · doi:10.48550/arxiv.2112.15513
openalex publication_date 2021/12/31 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We study mode-entanglement in the seniority model, derive analytic formulas for the one-body reduced density matrix of states with seniority ν= 0, 1, 2, and ν=3, and also determine the particle number dependence of the one-body reduced density matrix for arbitrary seniority. We carry out numerical calculations for the lightest calcium isotopes and for 94\rm Ru nucleus, and investigate the structure of their ground and low energy yrast states. We investigate the fulfillment of several predictions of the seniority model regarding the behavior of one-mode entropies, which we compare with the results of configuration interaction (CI) and density matrix renormalization group (DMRG) computations. For 94\rm Ru, the seniority model accounts for the 0g9/2 mode entropies, but seniority mixing is important for certain yrast states. Interaction induced quantum fluctuations decrease the occupation of the 0f5/2, 1p3/2 and 1p1/2 shells, and amount in finite mode entropies on these shells, too, clearly outside the scope of the simple (0g9/2)4 seniority model. The 0f7/2 shell based seniority model is more accurate for the light \rm Ca isotopes, but seniority mixing is substantial for some 44\rm Ca yrast states, too.