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Spherical to deformed shape transition in the nucleon-pair shell model
A study of the shape transition from spherical to axially deformed nuclei in
the even Ce isotopes using the nucleon-pair approximation of the shell model is
reported. As long as the structure of the dominant collective pairs is
determined using a microscopic framework appropriate to deformed nuclei, the
model is able to produce a shape transition. However, the resulting transition
is too rapid, with nuclei that should be transitional being fairly well
deformed, perhaps reflecting the need to maintain several pairs with each
angular momentum.Comment: 7 pages, 5 figure
Disorder effects on the spin-Hall current in a diffusive Rashba two-dimensional heavy-hole system
We investigate the spin-Hall effect in a two-dimensional heavy-hole system
with Rashba spin-orbit coupling using a nonequilibrium Green's function
approach. Both the short- and long-range disorder scatterings are considered in
the self-consistent Born approximation. We find that, in the case of long-range
collisions, the disorder-mediated process leads to an enhancement of the
spin-Hall current at high heavy-hole density, whereas for short-range
scatterings it gives a vanishing contribution. This result suggests that the
recently observed spin-Hall effect in experiment is a result of the sum of the
intrinsic and disorder-mediated contributions. We have also calculated the
temperature dependence of spin-Hall conductivity, which reveals a decrease with
increasing the temperature.Comment: 5 pages, 2 figures, Typos in the values of hole density correcte
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