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arXiv · 1607.08447

Momentum distribution of liquid 4He across the normal-superfluid phase transition

G. Ferré·R. Rota·J. Boronat
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Abstract

We have carried out a study of the momentum distribution and of the spectrum of elementary excitations of liquid $^4$He across the normal-superfluid transition temperature, using the path integral Monte Carlo method. Our results for the momentum distribution in the superfluid regime show that a kink is present in the range of momenta corresponding to the roton excitation. This effect disappears when crossing the transition temperature to the normal fluid, in a behavior currently unexplained by theory.

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G. Ferré, R. Rota, J. Boronat. 2016-07-28. Momentum distribution of liquid 4He across the normal-superfluid phase transition. https://doi.org/10.1007/s10909-016-1679-5

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