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arXiv · 1606.09056

Quantum Phase Transition in the Shape of Zr isotopes

Tomoaki Togashi·Yusuke Tsunoda·Takaharu Otsuka·Noritaka Shimizu
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Abstract

The rapid shape change in Zr isotopes near neutron number $N$=60 is identified to be caused by type II shell evolution associated with massive proton excitations to its $0g_{9/2}$ orbit, and is shown to be a quantum phase transition. Monte Carlo shell-model calculations are carried out for Zr isotopes of $N$=50-70 with many configurations spanned by eight proton orbits and eight neutron orbits. Energy levels and B(E2) values are obtained within a single framework in a good agreement with experiments, depicting various shapes in going from $N$=50 to 70. Novel coexistence of prolate and triaxial shapes is suggested.

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Tomoaki Togashi, Yusuke Tsunoda, Takaharu Otsuka, Noritaka Shimizu. 2016-08-05. Quantum Phase Transition in the Shape of Zr isotopes. https://doi.org/10.1103/physrevlett.117.172502

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