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arXiv · 0707.4094

Bounds for the Superfluid Fraction from Exact Quantum Monte Carlo Local Densities

D. E. Galli·L. Reatto·W. M. Saslow
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Abstract

For solid 4He and solid p-H2, using the flow-energy-minimizing one-body phase function and exact T=0 K Monte Carlo calculations of the local density, we have calculated the phase function, the velocity profile and upper bounds for the superfluid fraction f_s. At the melting pressure for solid 4He we find that f_s < 0.20-0.21, about ten times what is observed. This strongly indicates that the theory for the calculation of these upper bounds needs substantial improvements.

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D. E. Galli, L. Reatto, W. M. Saslow. 2007-07-27. Bounds for the Superfluid Fraction from Exact Quantum Monte Carlo Local Densities. https://doi.org/10.1103/physrevb.76.052503

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