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arXiv · 1801.04576

Polar phase of superfluid $^3$He: Dirac lines in the parameter and momentum spaces

G. E. Volovik
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Abstract

The time reversal symmetric polar phase of the spin-triplet superfluid $^3$He has two types of Dirac nodal lines. In addition to the Dirac loop in the spectrum of the fermionic Bogoliubov quasiparticles in the momentum space $(p_x,p_y,p_z)$, the spectrum of bosons (magnons) has Dirac loop in the 3D space of parameters -- the components of magnetic field $(H_x,H_y,H_z)$. The bosonic Dirac system lives on the border between the type-I and type-II.

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G. E. Volovik. 2018-01-14. Polar phase of superfluid $^3$He: Dirac lines in the parameter and momentum spaces. https://doi.org/10.1134/s002136401805003x

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