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arXiv · 0707.0954

Strong Coupling Correction in Superfluid $^3$He in Aerogel

Kazushi Aoyama·Ryusuke Ikeda
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Abstract

Effects of impurity scatterings on the strong coupling (SC) contribution, stabilizing the ABM (axial) pairing state, to the quartic term of the Ginzburg-Landau (GL) free energy of superfluid $^3$He are theoretically studied to examine recent observations suggestive of an anomalously small SC effect in superfluid $^3$He in aerogels. To study the SC corrections, two approaches are used. One is based on a perturbation in the short-range repulsive interaction, and the other is a phenomenological approach used previously for the bulk liquid by Sauls and Serene [Phys.Rev.B 24, 183 (1981)]. It is found that the impurity scattering favors the BW pairing state and shrinks the region of the ABM pairing state in the T-P phase diagram. In the phenomenological approach, the resulting shrinkage of the ABM region is especially substantial and, if assuming an anisotropy over a large scale in aerogel, leads to justifying the phase diagrams determined experimentally.

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Kazushi Aoyama, Ryusuke Ikeda. 2007-08-21. Strong Coupling Correction in Superfluid $^3$He in Aerogel. https://doi.org/10.1007/s10909-007-9487-6

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