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arXiv · 1902.00674

Effects of strong magnetic fields on neutron $^{3}P_{2}$ superfluidity with spin-orbit interactions

Shigehiro Yasui·Chandrasekhar Chatterjee·Muneto Nitta
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Abstract

We discuss neutron $^{3}P_{2}$ phases in the core of neutron stars in strong magnetic field (magnetars). The neutron $^{3}P_{2}$ pairing provides a wide variety of condensates, such as the uniaxial nematic and (D$_{2}$ and D$_{4}$) biaxial nematic, with different symmetries stemming from the combinations of spin and momentum. Based on the spin-orbital angular momentum coupling and the spin-magnetic field coupling of the neutrons, we derive the Ginzburg-Landau equation containing higher order terms of the magnetic field. We investigate the phase diagram of the neutron $^{3}P_{2}$ superfluidity, and find that the D$_{2}$ biaxial nematic phase is extended by the higher order terms of the magnetic field. We also discuss the thermodynamic properties, the heat capacity and the spin susceptibility.

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Shigehiro Yasui, Chandrasekhar Chatterjee, Muneto Nitta. 2019-02-02. Effects of strong magnetic fields on neutron $^{3}P_{2}$ superfluidity with spin-orbit interactions. https://doi.org/10.7566/jpscp.26.024022

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