Self-organization in He4 near the superfluid transition in heat flow and gravity

Syunsuke Yabunaka; Akira Onuki

doi:10.1103/physrevb.82.024501

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arXiv · 1004.0445

Self-organization in He4 near the superfluid transition in heat flow and gravity

Syunsuke Yabunaka·Akira Onuki

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Abstract

We investigate the nonlinear dynamics of He4 slightly below the superffluid transition by integrating model F equations in three dimensions. When heated from above under gravity, a vortex tangle and a sheetlike phase slip are generated near the bottom plate. Then a self-organized superfluid containing high-density vortices and phase slips grows upward into an ordinary superfluid. The thermal resistance due to these defects produces a constant temperature gradient equal to the gradient of the pressure-dependent transition temperature $T_{\lambda}(p)$. In this self-organized region, the temperature deviation $T-T_{\lambda}(p)$ consists of a negative constant independent of the height and time-dependent fluctuations. Its time-average is calculated in good agreement with the experimental value (W.A. Moeur {\it et al.}, Phys. Rev. Lett. 78, 2421 (1997)).

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Syunsuke Yabunaka, Akira Onuki. 2010-04-03. Self-organization in He4 near the superfluid transition in heat flow and gravity. https://doi.org/10.1103/physrevb.82.024501

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