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Superfluidity and Quantum Melting of para-Hydrogen clusters

Fabio Mezzacapo·Massimo Boninsegni
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Abstract

Structural and superfluid properties of para-Hydrogen clusters of size up to N=40 molecules, are studied at low temperature (0.5 K < T < 4 K) by Path Integral Monte Carlo simulations. The superfluid fraction displays an interesting, non-monotonic behavior for 22 < N < 30. We interpret this dependence in terms of variations with N of the cluster structure. Superfluidity is observed at low T in clusters of as many as 27 molecules; in the temperature range considered here, quantum melting is observed in some clusters, which freeze at high temperature.

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Fabio Mezzacapo, Massimo Boninsegni. 2006-07-27. Superfluidity and Quantum Melting of para-Hydrogen clusters. https://doi.org/10.1103/physrevlett.97.045301

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