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arXiv · 1208.3888

Different scenarios of topological phase transitions in homogeneous neutron matter

S. S. Pankratov·M. Baldo·M. V. Zverev
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Abstract

We study different scenarios of topological phase transitions in the vicinity of the π^0 condensation point in neutron matter. The transitions occur between the Fermi-liquid state and a topologically different one with two sheets of the Fermi surface. Two possibilities of a rearrangement of quasiparticle degrees of freedom are shown: the first-order topological phase transition and the second-order one. The order of the phase transition is found to be strongly dependent on the value of the critical wave vector of the soft π^0 mode. The thermodynamics of the system is also studied. It is shown that the topology of the quasiparticle momentum distribution is mainly determined by the neutron matter density, while the temperature T is essential in a narrow density region. A simple explanation of the first-order topological phase transition at T=0 is given.

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S. S. Pankratov, M. Baldo, M. V. Zverev. 2012-11-04. Different scenarios of topological phase transitions in homogeneous neutron matter. https://doi.org/10.1103/physrevc.86.045804

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