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arXiv · 1006.4279

Path Integral Monte Carlo calculation of momentum distribution in solid \^4\He

Riccardo Rota·Jordi Boronat
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Abstract

We perform calculations of the momentum distribution n(k) in solid \^4\He by means of path integral Monte Carlo methods. We see that, in perfect crystal, n(k) does not depend on temperature T and that is different from the classical Gaussian shape of Maxwell-Boltzmann distribution, even though these discrepancies decrease when the density of the system increases. In crystal presenting vacancies, we see that for T \ge 0.75K, n(k) presents the same behavior as in the perfect crystal, but, at lower T, it presents a peak when k\to0.

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Riccardo Rota, Jordi Boronat. 2010-06-22. Path Integral Monte Carlo calculation of momentum distribution in solid \^4\He. https://doi.org/10.1007/s10909-010-0249-5

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