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Pseudo-contact angle due to superfluid vortices in $^{4}$He

R. Luusalo·A. Husmann·J. Kopu·P. J. Hakonen
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Abstract

We have investigated spreading of superfluid $^{4}$He on top of polished MgF$_2$ and evaporated SiO$_{2}$ substrates. Our results show strongly varying contact angles of 0 - 15 mrad on the evaporated layers. According to our theoretical calculations, these contact angles can be explained by a spatially varying distribution of vortex lines, the unpinning velocity of which is inversely proportional to the liquid depth.

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R. Luusalo, A. Husmann, J. Kopu, P. J. Hakonen. 1999-10-24. Pseudo-contact angle due to superfluid vortices in $^{4}$He. https://doi.org/10.1209/epl%2Fi2000-00258-6

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