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arXiv · 0710.3940

A classical picture of the role of vacancies and interstitials in Helium-4

Ping Nang Ma·Lode Pollet·Matthias Troyer·Fu Chun Zhang
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Abstract

Motivated by experimental hints for supersolidity in Helium-4, we perform Monte Carlo simulations of vacancies and interstitials in a classical two-and three-dimensional Lennard-Jones solid. We confirm a strong binding energy of vacancies which is of the order of Lennard-Jones attraction. This is reminiscent of what has been found for vacancies in Quantum Monte Carlo simulations. In addition, we find a strong attraction and large binding energy of interstitials in two-dimensional simulations. This is mainly due to the formation of a pair of dislocations by clustering interstitials, in which minimizes the elastic deformation energy. We interpret the results in light of the properties of Helium-4.

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Ping Nang Ma, Lode Pollet, Matthias Troyer, Fu Chun Zhang. 2007-10-27. A classical picture of the role of vacancies and interstitials in Helium-4. https://arxiv.org/abs/0710.3940

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