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arXiv · 0807.4388

Simple, empirical order parameter for a first order quantum phase transition in atomic nuclei

Dennis Bonatsos·E. A. McCutchan·R. F. Casten·R. J. Casperson
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Abstract

A simple, empirical signature of a first order phase transition in atomic nuclei is presented, the ratio of the energy of the 6+ level of the ground state band to the energy of the first excited 0+ state. This ratio provides an effective order parameter which is not only easy to measure, but also distinguishes between first and second order phase transitions and takes on a special value in the critical region. Data in the Nd-Dy region show these characteristics. In addition, a repeating degeneracy between alternate yrast states and successive excited 0+ states is found to correspond closely to the line of a first order phase transition in the framework of the Interacting Boson Approximation (IBA) model in the large N limit, pointing to a possible underlying symmetry in the critical region.

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Dennis Bonatsos, E. A. McCutchan, R. F. Casten, R. J. Casperson. 2008-07-28. Simple, empirical order parameter for a first order quantum phase transition in atomic nuclei. https://doi.org/10.1103/physrevlett.100.142501

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