Quantum phase crossover in the spherical mean-field plus quadrupole-quadrupole and pairing model with two j -orbits

Bo Li, Anshan Normal University
Feng Pan, Liaoning Normal University
Xiao Xue Ding, Anshan Normal University
J. P. Draayer, Louisiana State University


The shape phase crossover in the mean-field plus the geometric quadrupole-quadrupole and pairing model within two j-orbits is analyzed, for which a simple description of 103-110Sn confined in the lowest 1d5/2 and 0g7/2 orbits above the 100Sn core is demonstrated to reveal the crossover behavior of the model. It is shown that B(E2; 41+ → 2 1+)/B(E2; 2 1+ → 0 g+), Q(41+)/Q(2 1+) and B(E2; 9/21+ → 5/2 1+)/B(E2; 11/2 1+ → 7/2 1+), Q(9/21+)/Q(7/2 1+) in this case may serve as effective order parameters for even-even and odd-A systems, respectively, from which the shape phase crossover from the rotation-like phase to the superconducting-like phase can be observed with variation of the number of valence neutrons.